SlideShare a Scribd company logo
国立大学法人	
  
           電気通信大学	
  
                                                                    振興調整費	
  
Unique and Exciting Campus
	
  



                 ネットワーク ラーニング
                   Network Learning
   AI-driven Connectivist Framework for E-Learning 3.0	
  




                             Neil Rubens
                             Active Intelligence Group
                             Knowledge Systems Laboratory
                             University of Electro-Communications
                             Tokyo, Japan
Evolution of eLearning: eLearning 1.0
eLearning uses technology to enhance Learning
                               ---------


‣ eLearning 1.0:
                               ---------
                               ---------
                               ---------
                               ---------




     ‣ reading: content became easily accessible

     ‣ logging: user’s activities could be logged and analyzed

  ‣ Learning Theories:

     ‣ Behaviorism: learning is manifested by a change in behavior,
       environment shapes behavior, contiguity

     ‣ Cognitivism: how human memory works to promote learning
Evolution of eLearning: eLearning 2.0
‣ eLearning 2.0:
                                       ---------
                           ---------   ---------
                           ---------   ---------
                           ---------   ---------
                           ---------   ---------
                           ---------




     ‣ writing: anybody can easily create content (e.g. blogs, wiki, etc.)

     ‣ socializing: interaction is easy (e.g. facebook, twitter, etc.)

  ‣ Learning Theories:

     ‣ Constructivism: constructing one's own knowledge from one's
       own experiences
       (enabled through writing)


     ‣ Social Learning: people learn from one another
       (enabled through socializing)
Network Learning: AI-driven Connectivist Framework for E-Learning 3.0
Network Learning: AI-driven Connectivist Framework for E-Learning 3.0
Broken Knowledge Cycle
‣ Problem: The current cycle of knowledge creation/utilization is inefficient !

  ‣ large portion of created content is never utilized by others*
        only 0.05% of twitter messages attracts attention (Wu et. al., 2011)
        only 3% of users look beyond top 3 search results (Infolosopher, 2011)

  ‣ large parts of created contents are redundant (Drost, 2011)

  ‣ Peak Social – the point at which we can gain no new advantage from social
    activity (Siemens 2011)
                                                              utilize
                                                    U0lized




                                  dge
                           no wle
                          K
                  is ting
                Ex
                                        Redundant




                                                              create
              Knowledge                             Novel
                                                                   *there are some personal benefits e.g. externalization, crystallization, etc.
Network Learning: AI-driven Connectivist Framework for E-Learning 3.0
Information Overload
                                    

                    for Computers 
                    not a Problem 
                    but an Opportunity




                                                                     Tan,	
  Steinbach,	
  Kumar;	
  2004	
  
500	
  Points	
         2,000	
  points	
      8,000	
  points	
  
Messaging Networks

How can we use computers to
learn in these settings?




                                                     http://datamining.typepad.com/photos/uncategorized/2007/04/08/twitter20070405.png




                                                                  Citation Network




                          Social Network




       hp://wiki.ubc.ca/images/f/ff/SocialWeb.jpg9




                                                                         hp://www.kieranhealy.org/files/misc/SocCoreCites.jpg:
Our	
  Focus	
  
informa0on	
  connec0vity	
  




                                                                               Nova	
  Spivack©	
  


                                                   social	
  connec0vity	
  
Connectivism (Learning Theory)
  
  Connec0vism:	
  Knowledge	
  is	
  distributed	
  across	
  a	
  network	
  of	
  
  connecTons,	
  and	
  therefore	
  learning	
  consists	
  of	
  the	
  ability	
  to	
  
  construct	
  and	
  traverse	
  these	
  networks	
  	
  (Siemens	
  	
  Downes,	
  2008)	
  

Property        Behaviourism                     Cognitivism              Constructivism     Humanism          Connectivism

Learning        Thorndike, Pavlov, Watson,       Koffka, Kohler, Lewin,   Piaget,            Maslow,           Siemens, Downes
theorists       Guthrie, Hull, Tolman, Skinner   Piaget, Ausubel,         Vygotsky           Rogers
                                                 Bruner, Gagne

How learning    Black box—observable             Structured,              Social, meaning    Reflection on     Distributed within a network, social,
occurs          behaviour main focus             computational            created by each    personal          technologically enhanced,
                                                                          learner            experience        recognizing and interpreting
                                                                          (personal)                           patterns

Influencing     Nature of reward, punishment,    Existing schema,         Engagement,        Motivation,       Diversity of network, strength of
factors         stimuli                          previous experiences     participation,     experiences,      ties, context of occurrence
                                                                          social, cultural   relationships

Role of         Memory is the hardwiring of      Encoding, storage,       Prior knowledge    Holds changing    Adaptive patterns, representative
memory          repeated experiences—where       retrieval                remixed to         concept of self   of current state, existing in
                reward and punishment are                                 current context                      networks
                most influential

How transfer    Stimulus, response               Duplicating knowledge    Socialization      Facilitation,     Connecting to (adding) nodes and
occurs                                           constructs of “knower”                      openness          growing the network (social/
                                                                                                               conceptual/biological)

Types of        Task-based learning              Reasoning, clear         Social, vague      Self-directed     Complex learning, rapid changing
learning best                                    objectives, problem      (“ill defined”)                      core, diverse knowledge sources
explained                                        solving
ConnecTvism:	
  
Nice	
  Theory	
  




Need:	
  
Tools	
  	
  Frameworks	
  
To	
  make	
  it	
  Prac0cal	
  

                                   hFp://imgs.sfgate.com/c/pictures/2011/12/19/ba-­‐BRIDGE20_SFC0105724887.jpg	
  
Methods	
  
Conceptual Framework




                                                                network
                                             Analysis Layer

        ---------
        ---------
        ---------
        ---------




                                                                connections
        ---------



 AI                             ---------
                    ---------   ---------
                    ---------   ---------
                    ---------   ---------
                    ---------   ---------
                    ---------
                                            Aggregation Layer




                                                                links
 use AI to:                                Linking Layer

 §  connect contents
 §  connect people




                                                                nodes
 §  connect people  contents
 §  connect models                      Extraction Layer




                                                                documents
Modules


                                Concept                  concept        concept
                               Extraction                 concept        concept
                                                            concept        concept
                                                             concept        concept

                                                                   concepts                                           Group Formation
      documents




                                                                                                           tasks




                                                                         concept      concept
                context
              (documents)
                                            Semantic                                  concept
                                                                         concept                                       Influence
                                            Mapping
                                                                                                                       Estimation
concept       concept
 concept       concept                                                   concept      concept
   concept       concept
    concept       concept
                                                                                                    interaction log
        concepts




                                                                                                                                                            network
                                                                                                                                         Analysis Layer



                                                                       concept            concept




                                                                                                                                                            connections
                                                                                                                                        Aggregation Layer
                                       Knowledge Level                 concept            concept
                                         Estimation




                                                                                                                                                            links
  concept        concept
   concept        concept
     concept        concept
      concept        concept                                           concept            concept                                         Linking Layer




                                                                                                                                                            nodes
          concepts
                                                                                                                                        Extraction Layer




                                                                                                                                                            documents
Analysis Layer                                                        Link Layer


Module
Pipeline




                                                                                    docs
                           want to learn about:
                                                   concept   Search Engine

(Example)

                                                               Concept                      concept            concept
               docs


                                                               Extractor                     concept            concept
                                                                                               concept            concept
                                                                                                concept            concept




                                                                                               concept                 concept

                      concept           concept                Semantic
                       concept           concept                                               concept                 concept
                         concept           concept             Mapping
                          concept           concept
                                                                                               concept                 concept




                      concept            concept


                      concept            concept              Search Engine

                      concept            concept                                                     concept             concept
                                                                                               …
                                                                              discussions           …        concept

                                                                                                   …         concept

                                                                                                         …     concept


                                                                                                …
                                                                                                         concept       concept
Sequence Diagram (Example)


user                                          system   user                                                system   user                                                system

        I want to know about term t_i                                                                                      I think t_i and t_k are similar ..
                                                              I want to know about term t_i and t_k
                                                                                                                           social

       semantics                                                   semantics
                      t_i
                                                                                   t_i                                     u_i: I think t_i is same as t_j …
                                   t_i
                                                                                                  t_i                         u_j: no t_is is more like t_p ...
                                                                                                                                  u_j: no t_is is more like t_p ...
          t_i               t_i
                                                                       t_i                 t_i                                u_m: I think t_i and t_k are similar ..
                                                                                                                                  u_i: you are right
                                  t_i
                                                                                                 t_i
                t_i
                                                                             t_i
                                                                                         t_i                               semantics               t_i
                                                                                                                                                                  t_i

       contents                                                    contents
                                                                                                                                       t_i                 t_i



                                                                                                                                                                 t_i
                                                                                                                                             t_i

                                                                                                                           contents                      t_i

       social                                                      social


                                                                                                                           social
        u_i: I think t_i is same as t_j …                          u_i: I think t_i is same as t_j …
          u_j: no t_is is more like t_p ...                         u_j: no t_is is more like t_p ...
       u_k: you are both wrong t_i is ...                              u_j: no t_is is more like t_p ...
                                                                                                                           u_i: I think t_i is same as t_j …
                                                                                                                              u_j: no t_is is more like t_p ...
                                                                                                                                  u_j: no t_is is more like t_p ...
                                                                                                                              u_m: I think t_i and t_k are similar ..
                                                                                                                                  u_i: you are right
Connecting Representations                                                                         ⇤
                                                                                                   V (d1 )




Semantic + Network
                                                                                                   ⇤
                                                                                                   V (d2 )
                                                                 ⇤
                                                                                                                                                                                  Type!             Network (N)!       Content (C)!           Proposed Hybrid!
                                                                 V (d1 )
                                                                                                   ⇤
                                                                                                   V (d3 )
                                                                 ⇤
                                                                 V (d2 )                                                                                                   Characteristics!
 This is a Title of a                                            !                         tfi,j = P
                                                                                                    ni,j
  Research Paper                                                 ⇤ (d
                                                                 V (d )1 )
                                                                 V
                                                                                                    k nk,j

         Joe Fakeman Jane Noman

                                         !                              3
                                                                                                                                                                              Analysis!
                                         V (d1 )
             Nowhere University
    {fakeman, noman}@nowhereuni.edu
                                                                                                          |D|
               Abstract                                                                idfi = log
        ~~~~~~~~~~~~~~~~~~~~~                                        ni,j                            |{d : ti ⌅ d}|
                                                            tfi,j = P
                                                                                                                                                                                                   !#$%$'()%*+(,(   !#$%$'()%*+(-(
        ~~~~~~~~~~~~~~~~~~~~~


                                                                 !
        ~~~~~~~~~~~~~~~~~~~~~
        ~~~~~~~~~~~~~~~~~~~~~
                                                                     k nk,j
Introduction
~~~~~~~~~~~~~~~~-
~~~~~~~~~~~~~~~~-
                    ~~~~~~~~~~~~~~~~~~
                    ~~~~~~~~~~~~~~~~~~                           V (d2 )                tf-idf i,j = tfi,j ⇥ idfi
                                                                                                                                                                                                                                              same as C   part of N
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
                                                                       |D|                                                                            ⇤
                                         !                                                                                                            V (d1 )
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~

                                                       idfi = log
                                                                                            !
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~



                                         V (d2 )
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
                                                                  |{d : ti ⌅ d}|
                                                                                           w (d1 )
                                                                                            V = tf-idf
                                                                                             i,j             i,j                                                           User Interface!
                                                                 !                                                                                    ⇤
                                                                                                                                                      V (d2 )                                                                                ./+$(/.(,(
                                                                 V (d3 )
 This is a Title of a                                    tf-idf i,j = tfi,j ⇥ idfi                    2            3
  Research Paper                                                                                     w1,j
                                                                                                   6 w2,j 7
         Joe Fakeman Jane Noman
                                         !                                               ⇤
                                                                                            !      6      7
                                         V (d3 )                                         V (dj ) = 6 . 7
             Nowhere University

                                                            wi,j = tf-idf i,j
                                                                                            V (d ) 4 . 5                                              ⇤
    {fakeman, noman}@nowhereuni.edu

               Abstract                                                                               .                                               V (d3 )
        ~~~~~~~~~~~~~~~~~~~~~
        ~~~~~~~~~~~~~~~~~~~~~
        ~~~~~~~~~~~~~~~~~~~~~
                                                                                                   2 wt,j
        ~~~~~~~~~~~~~~~~~~~~~                                        2          3
Introduction
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
                                                                   6
                                                                     w1,j
                                                                          7                                                                               ni,j
                                                                                                                                                                            Deployment!
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
                                                         ⇤         6 w2,j 7                                                                      tfi,j = P
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
                                                         V (dj ) = 6 . 7
                                                                   4 . 5                                                                                                                                                                     ./+$(/.(,(
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~

                                                                      .
                                                                                            !                                                             k nk,j
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~

                                                                     wt,j
                                                                                            V (d3 )
 This is a Title of a                                              ⇤         ⇤                                                                                 |D|
  Research Paper                                                   V (di ) · V (dj )                                                         idfi = log
                                                   sim(di , dj ) = ⇤         ⇤                                                                            |{d : ti ⌅ d}|
         Joe Fakeman Jane Noman
             Nowhere University
    {fakeman, noman}@nowhereuni.edu
                                                                   V (di ) V (dj )                                                                                           Execution

               Abstract
        ~~~~~~~~~~~~~~~~~~~~~
                                                                                                                                   ⇤                                          Speed!                                                         ./+$(/.(,(
                                                                                                                                   V (d1 )    tf-idf i,j = tfi,j ⇥ idfi
        ~~~~~~~~~~~~~~~~~~~~~
        ~~~~~~~~~~~~~~~~~~~~~
        ~~~~~~~~~~~~~~~~~~~~~

Introduction
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
                                                                                                                                   ⇤
                                                                                                                                   V (d2 )       wi,j = tf-idf i,j
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~-   ~~~~~~~~~~~~~~~~~~


                                                                                                                                                                           Reverse could also be done: i.e. converting textual representation to a network one.
                                                                                                                                   ⇤                      2          3
                                                   term-space                                                                      V (d3 )
                                                                                                                                                      6
                                                                                                                                                        w1,j
                                                                                                                                                                7
                                                                                                     1                                      ⇤         6 w2,j 7
                                                                                                                                            V (dj ) = 6   .     7
                                                                                                                                                          .
                                                                                                                              tfi,j =
                                                                                                                                       n
                                                                                                                                      P i,j
                                                                                                                                                      4   .     5                                           ⇥
                                                                                                                                ! k nk,j                w|T |,j                                     w1,j
                                                                                                                                V (d1 )                                                       ⇧             ⌃
                                                                    1
                                                                                                          !                                          ⇤         ⇤                              ⇧     w2,j    ⌃
                                                                                                          V (d1 )                        |D|
                                                                                                                          idfi = log sim(di , dj ) =
                                                                                                                                                     V (di ) · V (dj )                        ⇧      .
                                                                                                                                                                                                     .      ⌃                                  !
                                                                                                                                    |{d : ti ⌅ d}|   ⇤         ⇤
                                                                                                                                                     V (di ) V (dj )                          ⇧      .      ⌃                                  V (d1 )
                                                                                                                                !                                                             ⇧             ⌃                      !
                                                                                                          —                   V (d2 )                                                         ⇧ w|T |,j     ⌃                      V (d1 )
                                                                                                          —-
                                                                                                          ! Network Content based ⇥ idfi
                                                                                                                         tf-idf i,j = tfi,j                                         ⇥         ⇧             ⌃
                                                                                                          V (d2 )                                                                   V (dj ) = ⇧
                                                                                                                                                                                              ⇧
                                                                                                                                                                                                            ⌃
                                                                                                                                                                                                            ⌃                                  !
                                                                                                                                             wi,j i,j = (i, j) j)
                                                                                                                                               w = dist(i,
                                                                                                                                                                                              ⇧ w1,j        ⌃                                  V (d2 )
                                                                                                                              !=
                                                                                                                            wV (d tf-idf i,j                                                  ⇧             ⌃                      !
                                                                                                          —-                  i,j
                                                                                                                                     3 )                 2        3                           ⇧ w2,j        ⌃                      V (d2 )
                                                                                                          Generalized Assignment Problem
                                                                                                          !                                                  w1,j                             ⇧             ⌃
                                                                                                          V (d3 )                     2
                                                                                                          Objective: given a paper p, 1,j   ⇤
                                                                                                                                                3        6
                                                                                                                                            choose a 6 w2,jof 7
                                                                                                                                                         group
                                                                                                                                                                  7
                                                                                                                                                                  experts                     ⇧   .
                                                                                                                                                                                                  .
                                                                                                                                                                                                            ⌃                                  !          !
                                                                                                                                                                                                                                                          V (d1 )
                                                                                                                                         w V (d ) = 6
                                                                                                          M ⇥ M (of a fixed size6s) 2,j 7jcollectively (d )
                                                                                                                         ⇤               w that          4
                                                                                                                                                              ! possesses
                                                                                                                                                              .
                                                                                                                                                              .
                                                                                                                                                              V 5
                                                                                                                                                              .
                                                                                                                                                                  7                           ⇤   .         ⌅                                  V (d3 )
                                                                                                                          V (d ) = 6
                                                                                                                                      6         7                 1                                                                !
                                                                                                          the most expertise about p: .         7
                                                                                                                                j
                                                                                                                                    4 . 5.
                                                                                                                                                         w|N |,j                                w|N |,j                            V (d3 )
                                                                                                                                       wt,j            P
                                                                                                                         maximize R(M, p) = m2M r (m, p)                                     (1)                                                          !
                                                                                                                         subject to                 |M | =!(d )
                                                                                                                                                            s                                (2)
                                                                                                                                                                                                                                                          V (d2 )
                                                                                                                                    ⇤          ⇤
                                                                                                                                     V (di ) · V (dj )
                                                                                                                                                            V 2
                                                                                                          Challenge sim(di , dj ) = ⇤          ⇤
                                                                                                                                    V (di ) V (dj )
                                                                                                          Expertise is not additive:                   1                                                                                                  !
                                                                                                                                                X          !                                                                                              V (d3 )
                                                                                                                                  R(M, p) ⇤=                V (d3 .
                                                                                                                                                         r (m, p))                           (3)
                                                                                                                                                      m2M
                                                                                                          –
                                                                                                          Group Expertise Estimation
                                                                                                          Assumptions
                                                                                                          Mp are athors of paper p; so R(Mp , p) = 1, and
                                                                                                            ⇤                             ⇤

                                                                                                                       network-space
                                                                                                          R(M, p) = 0, where M ⌅ Mp = Ø.
                                                                                                                                    ⇤                                                                                          term-network-space
                                                                                                                                          M ⌅ M⇤
#pouf
                                #noel
                                      #deco
                                 #mobilier
                                         #facebook
                                                                                        Connecting Concepts                                                     #sustainable
                          #evenementiel                                                                                                       #savings
                          #twitter    #cadeau                                                                                  #reduce
                                   #buzz        #design                                                             #reuse
                                                                                                                                               #money



                                                                                                                                                                                                                                                                                                                                                 Modeling of: 
                            #inception                                                                                                                                                                                                                    #fuelcell
                                                                                                                                                                                                                                          #web
                                                                                                                                                                   #prop23                                                                             #hydrogen
                                                                                                                         #recycle
                                                                                                                                                                               #cleantech
                                                                                                                                                                                                                                           #mobile
                                                                                                                                                       #diy
                                                                                                                      #new       #florida


                                                                                                                                                                                                                                                                                                                                                 •  topics
                                                                                                                                                                                                                                           #pr     #innovation
                                                                                                                                        #california
                                                                              #news                                         #global               #home
                                                                                                                                                                                                         #biofuels
                                                                                                                                                                                                   #biofuel
                                                                                                                                                                                                            #greenroofs
                                                                                                                                                                                                                                    #publicrelations

                                                                        #boerse                #asia                              #blog                                                                #thermal
                                                                                                                                                                          #frugal
                                                                                        #biz                                                                                               #windenergy
                                                                              #aktien                                 #hot                         #business                          #greenit




                                                                                                                                                                                                                                                                                                                                                 •  lexicon
                                                                                                                               #gossip      #improvements    #budget     #cleanthinking        #nw
                                                                                                                                       #change                   #construction #lightingdesign
                                                                                                                                    #warming                                            #socent    #benefits
                                                                                                                                                                                                                     #finland
                                                                                                                                                                                                                                                                                             #tudelft
                                                                                                       #eco                        #ff

                                                                                                                                                       #green                                               #audit
                                                                                                                                                                                                                   #finance
                                                                                                                                                                                                            #ca #aia
                                                                                                                                                                                                                                                  #doe
                                                                                                                                                                                                                                                         #electric                     #cofely
                                                                                                                                                                                                                                                                                               #scriptie




                                                                                                                                                                                                                                                                                                                                                 •  semantics
                                                                                                                                                                                                                                                                                        #duurzaam
                                                                                                                                                                                                                   #architecture
                                                                        #health            #india                                                                                                     #efficient
                                                                                                                               #greenbuilding                                         #ecomonday
                                                                               #stock                                                                    #footprint
                                                                                                                      #renewableenergy




                                                                                                                                                                                                                   #energy
                                                                      #tips         #tip                                                       #carbon         #ev      #ecofriendly
                                                                                                                                                                                  #ac
                                                                                                                                                                                         #cancun



                                                                                                                                                                                                                                                                                                                                                 •  dynamics
                                                   #technology            #homes                                                          #israel                                    #china
                                                                                    #greentip
                                                                                                           #climate                                           #energyefficiency                                                                                                                            #delonghi


                                                                                                                                         #pv
                                                                                                                                              #solar                #canada
                                                                                                                                                                               #co2           #csr
                                                                                                                                                                                             #building #economist
                                                                                                                                                                                                                        #alternative
                                                                                                                                                                                                                           #education                                                           #btu   #45
                                                                                                                                                                                                                                                                                                             #dd45p #pt
                                                                                                                                                                                                                                                                                                           #dd50p    #50
                                                             #science                                                                          #re                                      #cleanenergy               #clean      #electronics         #cre                                         #10000 #lg
                                                                           #art                                                    #africa                                                                        #coal                                                           #dehumidifiers
                                                                      #novosti          #climatechange                                                      #conservation                            #electricity
                                                                                                                                                                                                                                  #cooperative
                                                                                                                                                                                                                                            #emissions                                            #edgestar    #star       #frigidaire
                                                             #animals
                                                                    #nasa                                 #environment                                 #cop16                            #efficiency
                                                                                                                                                                                                                                       #cville   #datacenter
                                                                                                                                                                                                                                                              #cdw                             #dehumidifier
                                                                                                                                                                                                                                                                                                            #rated
                                                                                                                                              #earth                                                        #dlr                                                                                                                         #pint
                                                                        #space                          #nature                                           #sustainability                                   #windpower
                                                                                                                                                                                                                                                                            #cars
                                                                                                                                                                                                                                                                                                        #65
                                                                                                                                                                                                                                                                                                           #microwave
                                                                                                                  #energysaving
                                                                                                                                                                                                                                                                     #it                                                                         #70
              #b
                                                                             #yahoo                                                         #sandiego                                 #economy                                                                                                                                                     #soleus
                     #c                                                                                                            #renewables                        #greenenergy                   #oil                                                                                                        #sd
                                                                #peakoil                                                                                   #ontario                                                   #startup                                                                                                              #dp1
             #a                                                                                                                  #un
                    #d                                           #neweconomy                                                                      #wef                                                          #encell       #vc                           #dimmer                                                                                   #air
                                                                                               #agw                 #water               #gobeyondoil #wcs                           #pakistan       #seattle
                                                                                                                                                                                                                                                       #ecosmart                                                                             #30
                                                                                                                                                                                                                                                                                                               #sunpentown
                                                                         #globalwarming                                         #unfccc     #energyrevolution                    #iea                       #solarpower                                                                                                    #ft
                                                                                                                                                                                                                                    #investment
                                                                                                           #us                                 #uk         #renewable                  #pkfloods
                                                                                                                                                                                                                                                                      #eecbg
                                                                                                                                                                                                            #platts                                        #lamp                         #hybrid
 #011013                                                                                                          #epa                                                        #transport
                                                                                                                             #solpwr10
         #pentair
#intelliflo                                                   #climategate        #socialmedia              #energystar
                                                                                                                                               #wind                                        #products                                                                  #led
          #vs                              #enviro                  #climaterealism                                                       #turbines
                                                                                                                                                                                      #living
                                                                                                                                                                                                         #power                                                                               #car
                                                                                                                                                                                                                                                                                                 #leaf
                                                                                                                                                 #offshore                                                                             #housing
                                                                                                                                #sun                                #greenjobs                                                                                                              #nissan
                                   #p2           #politics
                                                                                                #cnet
                                                                                                                                               #google
                                                                                                                                                              #career
                                                                                                                                                                                                             #meter #sunpower
                                                                                                                                                                                                                                                          #utility         #lighting
                                                                                   #tech                                                                 #london               #greentech                                 #tv
                                                                                                                                                                                                                              #europe
                                         #dems                                                 #apple                                                              #organic                                        #mass
                                                         #topprog                         #gadgets                   #travel                                                                                                   #greenliving
                                                                                                                                                                                                             #nuclear #eu
                                            #becktips                                   #gadget                                                                            #greenbuild     #smartgrid                        #texas
                                                                                 #dhilipsiva                        #baby                                                           #leed            #cisco        #rural             #free
            #gop                  #tcot           #obama
                                                                                  #technews
                                                                                                              #tfb
                                                                                                               #taf
                                                                                                                                #tcn
                                                                                                                             #cloud
                                                                                                                                         #media                                          #gridweek           #gas              #victoria
                                                                                                                                                                                                                                                                                                                                                 #3
                                                 #fail        #pledge
                                                                                                                  #livewithless                 #glam                                           #privacy          #save #lx               #streetlights
                       #ftrs                 #p21                                                                                                                               #careers                   #saving                     #r
                  #hhrs                                       #youcut                                                #thepowerofwaiting                                                                              #policy                            #leds
                             #rs                                                                 #winterhomeprep                #football    #veterans                                    #smartmeter                                #ledstreetlights
           #ocra                                                                                                    #lampe                                              #windworks                       #ghg       #sp1580                #momentive
                                                                                                                                #motiongraphics
   #tlot
                  #sgp                                                                                  #timelyadvice #win
                                                                                                   #underoath         #licht #clothdiapers #arm
                                                                                                                                                              #jobs  #ebc
                                                                                                                                                                                       #utilities
                                                                                                                                                                                                   #fuel
                                                                                                                                                                                                          #environmental
                                                                                                                                                                                                       #siemens
                                                                                                                                                                                                                                                    #light

                         #glennbeck       #tpp                                                       #disambiguation        #affiliate #linux                 #employment                                              #hayward                                                                                                                              #2    #9
    #twisters                                                                                                     #reddit                        #hiring    #46201
                                #912                                                                #geospatial                #marketing                                                      #fossil
            #teaparty                                                                                                 #rulez                        #engineering
                                                                                                                                                                                       #silver                                                                                                                                                          #6              #4
                                                                                                         #heatpumps     #heathrow                                                                                                                                                                                                                                 #1
                         #capandtrade
                                                                                                          #gis #saveenergy
                                                                                                                               #uksnow            #job                       #digguser             #fuels     #realestate      #pump
                                                                                                                                   #jobdanmark
                                                                                                                                                                      #in
                                                                                                                                                                                #digg   #gold
                                                                                                                                                                                                             #sale       #sp2610x15                                                                                                                      #5            #8
                                                                                                            #ontpoli #hohoho                                                                #mlfeeds
                                                                                                                                                                                #cdnprog
                                                                                                                                                                                                   #trhug
                                                                                                                                                                                                                                #super                                                                                                                            #7
                                                                                                      #stopglobalwarming #starbucks                                 #architekt   #cdnpoli
                                                                                                               #ondp
                                                                                                                                                   #tweetmyjobs       #calau
                                                                                                                          #vt       #cookies                                               #aps
                                                                                                                      #99                    #indee                                       #getinthegame
                                                                                                                            #photography        #indeed                                                    #credits          #haier
                                                                                                                             #pod            #sfo                                                               #tax #esncm053e
                                                                                                                                    #management                         #jobangels

                                                                                                                                                          #solarthermal   #grid               #meters
                                                                                                                                                     #breakingnews #accenture
                                                                                                                                                             #fb                         #smart
                                                                                                                      #wpccc                                                    #dms
                                                                                                          #cochabamba                                                                   #dsm
                                                                                                                                        #stocks                               #usa
                                                                                                                    #cmpcc                                                                 #noc
                                                                                                                 #bolivia              #cfd
                                                                                                                                              #mkt

                                                                                                                                                          #webhosting
                                                                                                                                                               #webhost
                                                                                                                                                       #greenwebhosting




Figure 7: Visualization (zoomable) of 416 Hashtags in Energy-Related Tweets, September 2010 Through
January 2011; created with Network Explorer (Rubens et al., 2011).


proaches that help understand the large scale conversations                                                                                                                                              enhanced word-of-mouth to stimulate user-generated per-
epilepsy

                                                                                                                                                                                                        differentiation




      Domain-specific
                                                                                  therapy
                                                                                                     surgery                                                                                         migration
                   atrial fibrillation                   glaucoma

                                                                                                                                                                                                      proliferation
                                                                                            review
                                         mri                               smoking
                                                                                                                                                                                                                   cytotoxicity
                                                                                                                                                                                                                 p53                                                    blood pressure




      Semantics
                                               echocardiography                                                                                                                                                                     reactive oxygen species                                        nutrition
                                                                                                                                                                                                     mitochondria
                                                                                                                                                                                                                                                                       hypertension
                                                                         gender                                                                                                                          apoptosis                        antioxidant                                             diet


                                                                                                                                                                                                                                  oxidative stress                     insulin
                                                       growth




                                                                    mutation                                                                                                                                                                                  diabetes
                                                                                                                                                                                                                                                                     physical activity
                                                                                                                                                                                                                                   infection
                                                                                                                                                                                                                                                                         metabolic syndrome 2 diabetes
                                                                                                                                                                                                                                                                                         type
                                                                                                                                                                                                metastasis
                                                                                                                                                                                                                                          sepsis                                   insulin resistance
                                                                                                                                                                                     radiotherapy
                                                  complications                                                phylogeny
                                                                                                                                                                                                                              cytokines                                 exercise
refrontal cortex                                                                                                                                                                         chemotherapy
                                                                                                                   evolution                          stress                                                                                                                                   body mass index

                                                                                                                                                                                                                          inflammation
                                                                    lung cancer

eeg
      fmri
                                                                                                                           gene expression
                                                                                                                                  microarray
                                                                                                                                                          anxiety
                                                                                                                                                                                                    cancer                                                                        obesity                                                                                                    metabolism
                                                                                                                                                        depression                                                                                         atherosclerosis
                                                                                                                                                                                                                                                                                                                                                                                    drinking water

                                                                                                                                                                                                                                                                                                                                                                                              bangladesh
ttention
                                                                                                                                    serotonin                        quality of life             chronic obstructive pulmonary disease
                                                                                                                                                                                                                                                                                                                                                                                      arsenic
                                                                                                                               dopamine
                                                                                                                                                                                                                                                   cardiovascular disease
                                                            perspective
                                          multiple sclerosis
                                                                                                                 schizophrenia                  breast cancer                                                                 copd

                                                                                                                                                                         education
                                           outcome
                                                                                                                                                                       ethics
                                                           laparoscopy
                                                                                                                                                     immunohistochemistry
                                                                                                                                                                          internet                                                                                                                                                                               fish
                    adherence                                                                                                                                       communication
                                                                                                                                                                                                                                                                                                                   adolescents                            mercury
                                           pediatric
                                                                                                                                                                    prognosis                                                                                        asthma
                                                                                                                                                                                             heart failure                                particulate matter                                                                                       lead
                    trauma                                                                                                                                               survival
                                                        fertility
                                                                                                                                                                                             myocardial infarction                                                                                                                                     cadmium
                                                                                                                                                                                                                                                   air pollution
                                                                                                                                                                                                                                                                                                                           environmental health
                                                                                                                                                                                                                                                                                                                                   environmental exposure
                                  antibodies

                                                                                                                                                                                                                   mortality                                           pregnancy
                                                                                                                                                                                health
                                                                                                                                                                                                         korea
                                                                                                                                                                                                                                                                                                                   children
                                                                                                                                                                                                                                                                                 child                                                                                                     occupational exposure
                                                                                                                                                                            climate change                                                                                                    polymorphism
                                                                                                                                                                            adaptation                                                                                                                                                                                                       polychlorinated biphenyls
                                                                                                                                                                                                                                                                                                                                          environment                                     pesticides
                                                                                                                                                                                                                                      public health                                          genetics



                                                                                                                                                                                                                                                        prevention                                                                                                                  biomarkers


                                                                                                                                                                                                                                                                                                                                                                        exposure

                                                                                                                                                                                                                          epidemiology
                                                                                                                                                                                                                                                                                                                                                                             biomonitoring




                                                                                                                                                                                                                                                   incidence

                                                                                                                                                                                                                                                                                                                                  india
                                                                                                                                                                                                                                                          hivrisk factors
                                                                                                                                                                                                                                                                     prevalence


                                                                                                                                                                                                                                                                 transmission
                                                                                                                                                                                                                                                                                                dispatch
                                                                                                                                                                                                                                                                                          outbreak                                  brazil
                                                                                                                                                                                                                                                                                                                                                          human

                                                                                                                                                                                                                                                              africa                                zoonoses

                                                                                                                                                                                                                                          tuberculosis
                                                                                                                                                                                                                                                           research                                                 surveillance
                                                                                                                                                                                                                                                                                                                   china
                                                                                                                                                                                                                                                                                                  antimicrobial resistance
                                                                                                                                                                                                                                                                                                                                   letter
                                                                                                                                                                                                                                                                                                                   viruses                                                pneumonia
                                                                                                                                                                                                  management
                                                                                                                                                                                                        diagnosis                                  molecular epidemiology                           bacteria
                                                                                                                                                                                              treatment                                                                                  west nile virus                                                                drug resistance
                                                                                                                                                                                                                                                                                                                    pcr

                                                                                                                                                                                osteoporosis                                                                                                      parasites               influenza
                                                                                                                                                                          elderly                                                                                                                                                            vaccine
                                                                                                                                                                                                                                                                                  genotype
                                                                                                                                                                                                                                                                                                               malaria               vaccination


                                                                                                                                                                                                                                                                                                                      disease outbreaks
P95-1032
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P91-1022                             W96-0201




Connection Formation
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     J93-1006                         W93-0301
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P96-1018          P93-1001
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 P00-1050

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             P97-1039

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              P97-1038 P93-1002



                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  P91-1023
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P94-1012
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        A97-1050

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                C98-1066
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            A94-1006

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   J97-2004                            J96-1001




Curriculum / Survey Design
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 C94-2178
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       C98-2129


                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             P97-1063
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P93-1003

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      H91-1026
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P93-1004
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     J93-1004




                                                                               Original Design:
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W95-0115




                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P06-1062




                                                                               
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               J00-2004
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           C98-2153




                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               W01-0505                  P95-1033
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   W03-0301
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      H05-1011




                                                                               Lacks Information
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P05-1057

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        J03-3002                                                                                                     W02-1012                                                                 C96-2141
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        P97-1037                                                                                                       W05-0812
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    J05-4003                                                               P06-2014                                      P06-1065
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          P07-1001

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         J93-1003                                                                                                                                  P04-1066

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 H05-1010                                                 N07-2022    C00-2163       P06-1097
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                D07-1006
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 W08-0409                                                                                 N06-1014




                                                                               
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       J07-3002
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     P03-1012                     P06-1009
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 H05-1012
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       N01-1026                                                                                                                                                                                                               C04-1006

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P06-1002

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           J90-2002
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     J93-2003                                                                  C04-1032
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              N06-1013       H05-1022
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 P07-1039




                                                                               Limited Diversity 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  P03-1041
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  H05-1009                                                                                                        D09-1050
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              E06-1019
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P07-1003                     P08-1010
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       W07-0715

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     H01-1035                        H94-1028                                                                                                                                         J04-2003                                                                                                               D07-1005 P09-3009

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                N06-1015
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                H05-1024                                                                                                                                                                                             W03-1001
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   W07-0711
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        J03-1005                                                        H05-1023
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             C04-1060                                                                                                                                       P05-1074




                                                                               Limited Context
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  W99-0604
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     W06-3123
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        D09-1040

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        P09-1104                                           N07-1061
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        N06-1003
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       W07-0403
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           C98-2225
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     D09-1141
                                                                                                                                                                                                                                                                                                                                        A88-1019
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    W02-1018
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             D09-1106
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    P02-1050                                                                                              W07-0709             P05-1059


                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    N09-1013                                                    P02-1039
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P00-1056                                                        J03-1002                                    P08-1012
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  N04-1021                                                                                        D08-1033
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          W09-0435                                                                                                                                                                   W08-0306
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       J00-1004                             P01-1030                          W07-0401
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  P07-1108                                                                                          P06-1067
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          P03-1019                                   D09-1105
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 W07-0716
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P05-1032
                                                                                                                                                                                                                                                                                                                                                                            J95-4004                                                                                                                                                                                                                                                                             W08-0307                                                          W05-0909
                                                                                                                                                                                                                                                                                                                                                                                                                                                                     P05-2016                                                                                                                             P01-1067                                                                          W06-1609
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                E06-1005
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  N07-1008                                      N04-1033
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   P03-1011
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     J97-3002                                                                                                  W09-1114
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            H05-1095

                                                                                                                                                                                                                                         W95-0107                                                                                                                                                                                                                                                                                                                                                                                                                                                                              E06-1032
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      D07-1038                               C04-1073                                                                                                                   N06-1004
                                                                                                                                  W05-0634
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W04-3207
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       D07-1030           W06-3108
                                                                                                                                             N04-1030                                                                                                                                                                                                                                                                                                               P96-1023                       J94-4004                                                                            P07-1020
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P02-1038
                                                                             C98-1013                                      P03-1002
                                                                                                                                                                 W04-3212                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               D07-1007
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        P02-1040                        C04-1030
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       D08-1066
                                                                                                                                                                                                                                                                                                                                                                                                                                           P06-1146                                                                                                                                                                                                                                                                                                                  W04-3250
                                                                                                               W04-2412                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      H05-1098 C04-1090
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P96-1021                                                                                      W06-3114                                                                                                                                            C08-1064


                                                       W03-1008                                     P05-1072
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           W04-3228
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         N03-1021                                              N04-1023
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W09-0809
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 D07-1055
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               N03-1017                                                      P05-1069
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     N06-1002

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         W04-1513                                W07-0718                                                                                                                                                                                       W09-0426
                                                                                                                                                                   W05-0620                                                  W00-0726
                                                                                                                                          J02-3001                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   W09-2310                                           D09-1136
                                                                                                                                                                                                                                                                                    W02-2018                                                                                                                                                                                                                                                                                                                              H05-1101                                                                                                                                                                                                                  P09-1106
                                                                                      P02-1031                        J05-1004
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W02-1039                                                                                                                                                                              W09-0434                                                                                                            D08-1011
                                                                                                                                                                                                                                                                                                                                                         J96-1002                                                                                                                                                                                                                                                                                                        P06-1091                                                                                                             P07-1005               D08-1089                                  N04-4026
                                                                                                               D07-1062                 P05-1073                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       J99-4005
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         W08-0302                                                                                                                              W08-0304
                                                                                           W03-1006
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W05-0908                                                                                                           J04-4002
                                                                                                                                                                                                                                        W06-1668
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              P07-1091
                                                                                                                                                   W06-2303
                                                                                                                                                                                                                                                                                                                                                                                                                                      J92-4003                                                                                                                                                                                                                                                                                                                                                                                                       H05-1021
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       P08-1115
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 J07-2003                                              W08-0403
                                               C04-1204
                                                                                                                            W05-1509
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        P04-1083
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     E09-1061                                    P05-1066
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   W06-3106
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     P03-1021                                            P07-2045
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  P07-1040
                                                                                                                                           N06-2026                                                 N01-1025                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           P07-1090
                                                                                                                                                                                                                                                                                                                                                                                                                                                      E09-1033                                                            W06-3104          W08-0308
                                                                                                                                                                          E03-1071                                                                                                                                                                                                                                                                                                                                                                                                                                                                         I08-2087                                         C08-1137
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   D09-1123                                                                                                                                                             P06-1098
                                                                                                                                                        N07-1070                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           I08-1066            P07-1002
                                                                                                                                                                                                                                                                                                                            P01-1017
                                                                      W03-1013
                                                                                                                                          W05-1511                                                                                                                                   H05-1099                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P08-1009
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      P06-1096            N06-1031                                               D07-1091                                                                                                                                                                                      D09-1114
                                                                                                                                                                                                        W05-1514                                                                                                                                                                                                                                                                                                                                                                                                                                                                 P06-1123                                                                                   D08-1010                                                   D08-1060
                                                                                                         W07-2208                                                                                                                                        N03-1028                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          D09-1037
                                                                                                                     H94-1020                           H05-1078
                                                     P02-1036                                                                                                                                                                                                                                                                        C92-2066

                                                                                                                                                                                                                                                                                                                  N03-1033                                 A00-1031                                                                                                                                                                                                                                                                             E09-1049
                                                                                                                                                                     J99-2004                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          P09-1036                       W08-0401                                                                                                     N07-1029

                                                                                                                                             C08-1050                                    N04-1032                                     W96-0213                W00-1320
                                                                                                                                                                                                                                                                          H05-1059
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W07-0405                                                                                                                           D07-1056
                                                                                        W03-0401                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 N06-1032                                             C08-1041
                                                                                                                                                              P06-1088                                                                                                                                 W97-0302                                                                                                                                                                                                                             W05-1507
                                                                                                                                                                                                                                                                                                                                                                                  N03-1016                                                                                                                                                                                                          P08-1024
                                                                                                                                      A00-2031                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   D08-1076
                                    P02-1043                      J97-4005                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P06-2101                                                                              N09-1029                                                                                                P09-1066       P06-1066
                                                                                                                                                                                                                                                                                                                                                     W02-1002                                                                                                                                                                                                                                                                                                   D07-1080
                                                                                                               W06-1619
                                                                                          P00-1058                                                                                                                                                   J01-2004
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   N04-1014
                                                                                                                                                                                                       J03-4003                                                                                                                                                                                                                                                                                                                          D08-1012                                                                                 W07-0702
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           N09-1025                                                         D07-1077
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       W07-0701
                                                                                                                                                                                                                                                                         P02-1034
                  J07-4004                           C04-1041
                                                                                                                                       P99-1069                                                                                         J05-1003
                                                                                                                                                                                                                                                                                                                                       P07-1120                                                                                                                                                                                                                                                                                                        N04-1022                                                                       D07-1104
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       P05-1033
                                        P03-1046                                                                                                                                                                                                                                                                                                    N06-1040                                                                                                                                                                                                                           D09-1023                                                                                                                                                                                                                                          D09-1073
                                                                                                                                                                                                                                                                                                      P05-1039           W98-1115                                                                                                                                                                                                                                                                                                                                                                                  W07-0706
                                                                                                                                                                         P00-1061                     W09-0103                                                                                                                                                                                                                                                                         D07-1003                                                                                                                                                                       W06-3119
                                                                                                   N06-1019                                                                                                                                                                                                                                                                                                                          P09-1042                                                                                                                                                                     D09-1021         D08-1065                                             D09-1008                                                 W09-0424
                                                                                       N04-1013                                                                                                                                                                P97-1003                                                                                                                        W02-1001                                                                                                                                                                                                                                                                                                                                                   C08-1127
                                                                                                                                                                                                                                                                                                                                  P92-1017                                                                                                                                                                                      N06-3004
                                                                                                                                                 W07-2202                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   C08-1144                                            W09-2306
                                                                                                                            P02-1035                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    N06-1033
                                        W04-3215
                                                                 P05-1011                                                                                        D08-1008                                         A00-2018                                                                                                                                                                                                                                                                                                                                                                                     W06-1628
                                                                                                              P04-1014                                                                                                                                         D09-1119
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   D08-1024
                                                                                                                                                                                                                                                                                                                                              J98-2004
                                                                                                                                                                                                                                                                                                                                                                                                                                        H05-1036                                                                                                                                                                                                                                         D07-1079                                                                                                                   P06-1077
                             P02-1042                                                                                                                   P01-1010                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        P09-1103
                                                                                                                                                                                                                                                                    W05-1515
                                                                      N06-1024
                                         J07-3004                                                                                        N03-1014                                                                                                                                                                                 N06-1022                                                                                                                                                                                    W06-1608                                                                                                                                                                                                                   W08-0402
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            P05-1034
                                                                                                  W04-2003                                                                   P95-1037
                                                                                                                                                                                                                                                                                                                                                                                                    P99-1059
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           N09-1027                   D09-1108                                                    P06-1121                                       E09-1044

                                                                                     P07-1032                                  W07-1202                                                                 P08-1037              J93-2004                                          W00-1201
                                                                                                                                                                                                                                                                                                                                                                      W06-1666
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            P09-1087                P08-1025                                                                                        P09-1020
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    N09-1049

                                                                                                                                                                                                                                                                                                                                              H05-1064                                                                                                                                                                                                                                                                        N04-1035
                                                                                                                                                                                                                                                                                                            W06-1638
                                         W03-1005                                                                                                                                                                                                                                         P03-1056
                                                                                                                                                                                                                                                                                                                                                                                                                          D08-1093                                                                  J99-4004
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              D07-1078                                                                                                                     P03-2041          N07-1063
                                                      P04-1041                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        P07-1089
                                                                                                                                                                                                                              P01-1042
                                                                                                                                                            W97-0301                         J98-4004
                                                                                                                                                                                                                                                                                                                                         W06-1615
                                                                                                                                                                                                                                                                                                                                                                      P03-1054                                                             P96-1024
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       C08-1138               P08-1114                 P09-1065
                                                                                                         P96-1025                                                                                                                                                        P05-1038                           W04-3224
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               W06-3601
                                                                                                                                                                                                                                                                                           D09-1135
                                                                                                                                                                               E09-1090
                                        P02-1018                                                                                                                                                                    P04-1015                       D09-1059                                                                                                                                                                                              D09-1127
                                                                                     P04-1042                                                                                                                                                                                                                                                   W06-2904
                                                    D07-1027                                                                                            H91-1060                                                                                                                                                                                                                                                                                                                                                                                                                                                                                P08-1066
                                                                                                                                                                                                                                      C02-1126                       W09-1008                                                                                                                                                                                                                                                                                                                  N09-1026                                                                                                                                                                                     P08-1064
                                                                                                                                                                                                                                                                                                                                                                                                               I05-1007

                                                                                                                                                                                 P05-1023
                                                                                                                                                                                            W07-2219
                                                                                                                                                                                                                                                                                                 P05-1022
                                                                                                                                       E03-1005                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  P09-2035
                                                    P03-1055                                                                                                                                              W01-0521                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                W06-1606
                                                                             P04-1082                                                                    P06-1110
                                                                                                                                                                                                                                                                     J04-4004                                                                                                                                                                                                                                                                    P05-1067
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               P09-1064
                                                                                                                                                                         P03-1013
                                                                                                                                                                                                                                       H05-1100                                                                                                             N07-1051                                                                                                                                                                                                                                                                                                               P07-1019
                                                                                                                                                                                                                           P06-2089                                                                             D09-1161                                                                                                                                                                                                      W05-1506
                                                                                                                                                                                               W06-3603
                                                                                                                                                                                       P07-1080                 W05-1512                                                                                                                                                                                                                               E09-1037
                                                                                                                                                                                                                                                                                                 P05-1044                                       W05-1504                                     P04-1061
                                                                                                                                                              D09-1085                                                                                                                                                                                                 P06-1072
                                                                                                                                                                                                                                                                         D08-1091
                                                                                                                                                                                                                                 P08-1109
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        D08-1022
                                                                                                                                                                                                                                                                                                                 P07-2052
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               P08-1023
                                                                                                                                                                                                                                            N06-1020                                                                                                                                                                                                                                                                                                                                                                                                       P09-1063
                                                                                                                                                                                                                                                                                                                                                              N06-1021
                                                                                                                                          H92-1026
                                                                                                                                                                                                           P08-1006                                                      W04-3201
                                                                                                                                                                    P04-1013 W05-1513                                                                                                                                                        P06-1055                                               P08-1067
                                                                                                                                                                                                                                                                                                 P05-1010
                                                                                                                                             P07-1079
                                                                                                                                                                                                                                            W08-2102
                                                                                                                                                                                                                                                                                                                   P09-1059

                                                                                                                                                                                                                P06-1033                                                                                                           W09-1104
                                                                                                                                                            P06-2041                                                                                                                                 D09-1087

                                                                                                                                                                                                                                                                                    N07-3002
                                                                                                                                                                                    W05-1505                                                           P06-1043
                                                                                                                                                                                                                               E03-1008
                                                                                                                                                                                                                                                                     W05-1516

                                                                                                                 P99-1065
                                                                                                                                                                            C08-1081                                                                                                                                                                                                               D08-1016
                                                                                                                                                  J08-3003                                                                                                                                                                                                   P09-1041
                                                                                                                                                                                                                                 W07-2217


                                                                                                                                                                                                                                                                                                                       P09-1007
                                                                                                                                             C08-1095
                                                                                                                                                                                                                                                                                                                                     P05-1012
                                                                                                                                                                               W07-2218
                                                                                                                                                                                                       D07-1111
                                                                                                                                                                                                                                          C96-1058
                                                                                                                                                                                                                                                                                                        P08-1061
                                                                                                                                                                                                                                                                                                                                                                                                        D07-1070
                                                                                                                                                 C04-1010




                                                                                                                                                                                                                                                                                                                                                                                                                                                 Revised Design:
                                                                                                                                                                                                                                                                            P08-1068                                                                                   P09-1039



                                                                                                   E06-1010                                                                                                       I08-2097
                                                                                                                                                                                                                                                                                                  D08-1059                                                                             D07-1014
                                                                                                                                                                                                                                                     D09-1060
                                                                                                                                                                                                                                                                            D07-1101
                                                                                                                                                                            P07-1122                                                    N07-1049
                                                                                                                          P05-1013
                                                                                                                                                                                                                                                                                                                                                                      W06-1616
                                                                                                                                                                                                                                                                                                   D09-1058
                                                                                                                                                                                                     N06-2033
                                                                                                                                                      D07-1099
                                                                                                                                                                                                                                                                                      D07-1015




                                                                                                                                                                                                                                                                                                                                                                                                                                                 Information Criterion-based
                                                                                                                                                                                                                                                              E06-1011
                                                                                                                                                                 W06-2922
                                                                                                                                                                                                                                                                                                                                   W07-2216
                                                                                                                                                                             D07-1119                                                         I08-1012
                                                                                                                                                                                                                                                                                                                 D08-1017

                                                                                                                                                                                          W06-2920
                                                                                                                                       J08-4003

                                                                                                                                                                                                                   D07-1096
                                                                                                                                                   W04-2407                                                                                                                         P08-1108

                                                                                                                                                                                           D07-1097                                   D07-1013
                                                                                                                                           N07-1050
                                                                                                                                                                   W06-2933
                                                                                                                                                                                                     N09-2066
                                                                                                                                                                                                                             H05-1066
                                                                                                                                                                                        P09-1040
                                                                                                                                                                                                                                              W06-2932
Connecting/Pruning Nodes
        Network Structure Learning
                                                                                         
                                                                                                                                                                                                                                                                                                                                                                                                                             
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        Proposed Method Proposed
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     Proposed Method       Propo



                              Learning in Collaborative Settings                                                                                                                                                                                                                                                                                                                         Network Structure Learning                                                                              yt+1 yt+1                                                  yt+1

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 yt    yt                                                   yt
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            input index
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     input index
                input index




                                        input index




                                                                                                            input index


                                                                                                                                   input index




                                                                                                                                                                                                                                                                                                                                                                                            input index




                                                                                                                                                                                                                                                                                                                                                                                                                       input index
                                                                                                                                                                                                                                                                                                                                                                                                                                     Model


                                                                                          0.4
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          a)a) Adding training point causes many b)
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            Adding training point causes many b) Ad
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          output estimates toto change.
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            output estimates change.              out
                              output                         feature index                                    output                                                                                   feature index                                                                                                                                                                                      output                     feature index
                                                                                         0.35
                                                                                                                                                                                                                                                                                                                                                                                                                                        SL                                                                                      outpu
                                      Traditional                                                                                                                                   Collaborative                                                                                                                                                                                                                                                                       Proposed Method Proposed Approach
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           Proposed Approach
                                                                                                                                                                                                                                                                                                                                                                                                                                                                     Proposed Method
                                                                                          0.3




                                                                                         0.25
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           Proposed Approach
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         Proposed Approach
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                yt+1 2
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         Use ychanges in in the estimates ⇥yt yt+1 ⇥2⇥to
                                                                                    P (yt+1 )


          Learning in Black-box Settings                                                  0.2                                                                                                                                                                                                                                                                                                                                                                                              Use changes the estimates ⇥yt
                                                                                                                                                                                                                          Figure 5: T1 =⇤yt yt+1 ⇤ and the                                                                                                                                                 yt+1   yt+1                                                                     y       t+1

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           generalization error G d )
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         generalization error G (x(xd )
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             t+1
                                                                                                                           0.4


                                                                                                              0.4                                                                                                         value that it tries to approximate ⇥G
                                                                                         0.15
                                                                                                                                                                                                                                                                                                                                                                                                                  yt                                                                       y y
                                                                                                                          0.35
                                                                                                                                                                                                                          (Section Section 3.1). Most importantly,                                                                                                                                         yt                                                                                t
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   t


                                                                                          0.1
                                                                                                            0.35


                                                                                                                           0.3                                                                                            high values of ⇤yt yt+1 ⇤2 should cor-
                                                                                                                                                                                                                                                                                                                                                                                                                                                            input index
                                                                                                                                                                                                                                                                                                                                                                                                                                                     input index
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           where yt+1 are the estimates after d , y, ) )
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         where yt+1 are the estimates after (x(xd d ydw
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      input index
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               input index

                                                                                                       16%    0.3
                                                                                                                                                             84%                                                          respond to high values of ⇥G, since
                                                                                                                                                                                                                          those are the points that are likely to be
                                                                                                                          0.25


                                                                                                            0.25 P (yt+1 )


                                                                                                                                                                                                                          chosen.
                                                                                         0.05
                                                                                                    P (yt+1 )              0.2


                                                                                                              0.2
                                                                                                                                                                                                                     Figure 5: T =⇤y   y ⇤ and the                                       1                   t              t+1

                                                                                                                          0.15
                                                                                                                                                                                        Figure 5: that it tries to t+1 ⇤ and the ⇥G
                                                                                                                                                                                             value T1 =⇤yt y approximate
                                                                                           0
                                                                                                            0.15
                                                                                                                                                                                        value(Section tries to 3.1). Most importantly,
                                                                                                                                                                                              that it Section approximate ⇥G
                                                                                                                                          y                                         y
                                                                                                                                                                                             high values of ⇤yt yt+1 ⇤2 should
                                                                                                                                                                                        (Section Section 3.1). Most importantly, cor-
                                                                                                                                                                                                      9
                                                                                                                           0.1
                                                                                                                                  16%                                  84%              high values of to high t+1 ⇤2 should cor-since
                                                                                                                                                                                             respond ⇤yt y values of ⇥G,                                                                                                                                                 Proposed
                                                                                                              0.1                       yt+1                                                                                                                                                                                                                             A−optimal
                                                                                                                           16%                               84%                        respond toare thevalues of ⇥G, likely to be
                                                                                                                                                                                             those high points that are since                                                                                                                                            D−optimal

                                                                                                                                                                                        thosechosen. 8points that are likely to be
                                                                                                                                                                                              are the
                                                                                                                          0.05                                                                                                                                                                                                                                           E−optimal
                                                                                                                                                                                                                                                                                                                                                                         Transductive

                                                                                                                                                                                        chosen.
                                                                                                            0.05
                                                                                                                                                                                                                                                                                                                                                                         Random
                                                                                                                                                                                                                                                                                                                                                                         Optimal

                                                                                 Figure 3: Distribution of the ⇥          estimates
                                                                                                                            0
                                                                                                                                                         y                          y
                                                                     ⇥                                           0                                                                                                                        9                                7
                                                                                                                                                                                                                                                                                                                                                 Proposed


                                                                                 yt+1 in relation to the estimate yt and the
                                                                                                                                                 y                          y
                                                                                                                     y                                    t+1                                                9
                                                                                                                                                                                                                                                                                                                                                 A−optimal
                                                                                                                                                                                                                                                                                                                                                 D−optimal
                                                                                                                                                                                                                                                                                                                                    Proposed
                                                                                                                                                                                                                                                                                                                                                 E−optimal
                                                                                                                                                                                                                                                      Mean Squared Error




                                                                                                                y                                t+1                                                                                      8                                                                                         A−optimal
                                                                                                                                                                                                                                                                                                                                                 Transductive

                                           f (x)                                                         f (x)
                                                                                 true value y.xFigure 3: Distribution of y estimates
                                                                                                                                                                                                                                                                                                                                    D−optimal
                                                                                                                                                                                                                                                                                                                                                 Random
                                                                                                                                                                                                                                                                           6                                                        E−optimal

                               x
                                                                                                                                                                                                             8                                                                                                                                   Optimal

                                                                     yx                                                  the
                                                                                                                                                                                                                                                                                                                                    Transductive

                                                                                                                                                                   x                                                                                                                                                                Random

                                       yx =                                                                    yx =
                                                                                                                                                                                                                                          7

                                                         ·x          ⇥                                                     x
                                                                                                 Figuret+1 in relation to·the estimate yt and the
                                                                                                      y 3: Distribution of the estimates                                                                     7
                                                                                                                                                                                                                                                                                                                                    Optimal
                                                                                                                                                                                                                     Mean Squared Error




                                                                                                      true value y.
                                                                                          ˆ yt+1 in relation to the estimate yt and the
                                                                                                                                                                                                                                          6                                5




                                                                                                                                                                                                                                                                                                                                                                                           a)a) Adding training point causes many b) Adding training point causes few
                                                                                                                                                                                        Mean Squared Error




                                                                                          yt+1 true value y.
                              (a) White (x) Model.
                                      f Box                                                       (b) Black Box Model.
                                                                                                                                                                                                                                                                                                                                                                                             Adding training point causes many b) Adding training point causes few
                                                                                                                                                                                                             6



                               x
                                                                                                                                                                                                                                          5

                                              yx                                           ˆ
                                                                                           yt              ˆ
                                                                                                           y                     y*
                                       yx =              ·x
                                                                                                                            t+1                                                                                                                                            4
                                                                                                                                                                                                             5

                                                                                                              ˆ
                                                                                                              yt+1

                                                                                                                                                                                                                                                                                                                                                                                             output estimates to change.         output estimates toto change.
                                                                                                                                                                                                                                                                                                                                                                                                                                   output estimates change.
                                                                                                                            ˆ
                                                                                                                            yt                                          y*      c
    Figure 4: For Black Box models only the inputs and outputs
                                     a                   b                                                                                                                                                                                4




                                                                                                                                                                                                                                                                                                                                                                                           output estimates to change.
                                                                                                                  a                                  b             *            c
                                                 ˆ
                                                 y                          y                                        t                                                                                       4




           (b) Black Box Model.
                                                                                                                                                                        c                                                                                                  3
                                                                                                   a                                b                                                                                                     3



    are accessible, internal workings areFigure after4:after after training unlike for
                                  Figure 4: not accessible, point
                                              yFigure the training point
                                                           y        the training
                                               is added to the training set point
                                                  4: y        the             (making the
                                                                                                                                                                                                             3




                                  is added toadded to the training set (making the the
                                           is the training set (making
                                                                                                                                                                                                                                          2
                                                                                                                                                                                                                                              1             2                      3         4        5          6          7            8        9         10




models only themodels [11].outputs of trainingofpoints points equal to t+1).
    White Box inputs and                       number
                                                                                                                                                                                                                                                                                                    Training Set Size
                                                                                                                                                                                                                                                                           2
                                                                                                                                                                                                             2                                                                 1              2 6            3                  4              5          6      7   8    9         10
                                                                                                                                                                                                                 1                        2       3                            4         5                   7          8            9         10


                                  number number of training pointsequal to t+1).
                                                                     equal to t+1).
                                                                                                                                                                                                                                                                                                                                                                                             Proposed Approach
                                                                                                                                                                                                                                                                                       Training Set Size                                     Training Set Size



 kings are not accessible, unlike for                                                          Figure 6: Evaluation of active learning
                                                                                          Figure 6: Evaluation of active Error: lower
                                                                                               criterions (Mean Square learning
                                                                                                                                                                                        criterions (Mean Square Evaluation at active learning
                                                                                                                                                                                              values are better, values are different of
                                                                                                                                                                                                                                                                                                                                                                                           Proposed Approach
         yt+1                                                                                          yt+1                                                                                         Figure 6: Error: lower
                                                                                                                                                                                                                                                                                                                                                                                                                                 yt+1 2 estimate improvement in the
                                                                                                                                                                                              the statistical significance level of 95%).
                                                                                                                                                                                        values are better, values are different at
                                                                                                                                                                                                    criterions (Mean Square Error: lower
                                                                                                                                                                                                                                                                                                                                                                                           Use changes in in the estimates ⇥yt yt+1 ⇥2⇥toto estimate improvement in the
                                                                                                                                                                                                                                                                                                                                                                                             Use changes the estimates ⇥yt
         yt                                                                                            yt
                                               input index                                                                                               input index                    the statistical significance level of 95%).
                                                                                                                                                                                                                                                  values are better, values are different at
      a) Adding a training point
                               yt+1

                               yt
                                                                                                b) Adding a training point                                                                                                                        the statistical significance level of 95%).                                                                                                 generalization error G d )
                                                                                                                                                                                                                                                                                                                                                                                           generalization error G (x(xd )
      influences many output es-                                input index

                                                                                                influences only a few output
t+1                                     f (x)                      1 + x A x ⇤G                                                           p
                                                                          J      1          ⇤         1                                                                           ⌅ A = X⇤ X + I A = X⇤ X + I
                                                                  xx A    A                                                                                                         X⇤ X =
                                                                                                                                                                                        ⇥i i ⇤ ,

         Conceptual Justifications
                (A + x x⇤ ) 1                        = A f1                                                                                                                                        i
                                                          (x)               .                                                                                                                     ⌅p                              ⌅  p

                                                              1 + x⇤ AJ(⇥) = ⌅⌅t
                                                                       1x
                                                                              y                            ⌅1
                                                                                                           yt+1 ⌅ .⇤2
                                                                                                                                                                                   i=1
                                                                                                                                                                                            =           ⇥          ⇤
                                                                                                                                                                                                                     + I.      =          ⇥i i ⇤ + I. i
             2
                          ⇤ t+1 = (A + x⇤x⇤1 1 (X⇤ y + x 1y )⇤                                                                  1 ⇥i ⇤                                          ⇥1 ⇥2 . . . pi ⇥im i ⇥m+1 =i=1 . = ⇥d =
                                                                                                                                                                                                                                    ..
                        B                     T1 V ) ⇤                                                A xx 0             A X y                                                                    i=1⌃ p
                                                                                                                                                                                     m a ⇥ 1 1 ⌃x⌅ ⌅ . 2                   ⇥2 ⇥ X⇤ X
                               (A + x x ) ⇤ X ⇤G A X y ⇤ 1         y=                                                                                                    i
                                                                                                                                                                                              a⇥
                                   2 (A + x x ) 1 X⇤ y + (A + x x ) x1y . x A
                        E G = = + B + V,
                                                                                                               + ⇤ 1x                                              A
                                                                                                                                                                                                                   ⇥ xi
                                                                                                                                                                                                                         ⇥    i    .              JO
   2
           BJ                     V                                                                                                           ⇤     1
                                                                                                                                           x⇥ A x⇥ = a ⇧ ⇥                 x⇤ A 1 x⇥ = a i=m+1         JO i=m+1                           JO
                        ⇥
                                                                     A 1 x x⇤argmax⇤J(⇥).
                                                                                        A 1X y                                                                  1       p⇧p            ⌅
                                                                                                                                                                                              ⇥2 ⇥
     (A + x x⇤2) 1 X⇤ y = A 1 X⇤2y n                                                                                                                                    i=m+1 x⇥ x⌅ i
                                                                                                                                                                      1                              2                                         x⇥ x⇥
                                                                                                                                1                                             i=m+1        ⇥
                                                                                                                                                                                            i
                                                                                                                                                                          ⌅ ⇤X + I
          E G = +J(⇥) = ⌅⌅ B + V, y                       {⇥.i }i=1 1 + x A 1 x      ⇤                                                                          A = XX⌅ X
                                                                                                                                                                       XX                              { { p 2}p
                                                                                                                                                                                                             }i=m+1                              a2              x
                                          t     ⌅
                                                yt+1 ⌅                                                                                                                                                     i
                                                                                                                                                                                                               a i i=m+1⌅ J =
           ⇥
                      ⇤ (A + x x⇤ ) 21 x y = A 1 x y
                                               ⌅                                             A 1 x x⇤ A %-1#x y         '#
                                                                                                                          ,#                                              ⌅ p                  JO =                  2  . X X⌅ X XO
                                                                                                                                                                                                                                           (a + 1)
                                                                                                                                                                                                                                                          . i}
                                                                                                                                                                                                                                                         2{ {

                                        {⇥i }n ⇤ 1                                  1        ⇤3       1         / +$,
                                                                                                              ⇤#)$* 1
                                                                                                                                   .
                                                                                                                                  . .,/')-'##,# JO JO                 =          ⇥i i ⇤ + x⇥ (a + 1)
                                                                                                                                                                                          i          I. x
                                                                              A x x 1A + x'%' A x51
                                                                                                                                                                                                             ⇥
          B=             E f (x) + x i=1 ) = A 1
                                (A g(x)x q(x)dx,                                                        . (                                                    JO i=1                             JO
         ⇤               ⇥     ⌅2                                  1          1A x y1(1-
                                                                             ⇤ + x⇤ A 3 1 x                       2
                   D
                               argmax J(⇥). A x x !#$%'                                                                                 a                               a                                              JO                    a
             x⇤ ) 1 ⇤y
B = + x E f (x) xg(x) = A x y
 (A                                q(x)dx,
                                          1        ⌅2
                                                                            ⇤         1x 3
                                                                                                   . 3           0$1             0
                                                                                                                         x⇤ A 1 x⇥ = a                 a                         JO a                                                             JT JT
       D V⇥ = E            f (x) E f (x) q(x)dx. x A             1+                           14        16                 ⇥                                                   JO
                                                                                                                                                                                                                     JT JT
            ⇤ ⇥ D                 ⌅2 ⇥
                              ⇤ ⇤ q(x)dx.
                  ⇤ E f (x) =A1 1 x y                           A 1 x x⇤ A 11 x y                  ⇤
                                                                                                                    1
                                                                                                            1A ⇤ x x A
                                                                                                                             ⇤        1 ⇤
                                                                                                                                       X y                      (1 + x⌅ A⌅ A ⇥1 x⇥ )2 1 1 ⌅
                                                                                                                                                                      (1 +⌅ xa2
                                                                                                                                                                            ⇥ x
                                                                                                                                                                                    1
                                                                                                                                                                                         )2                      p
              f (x)t+1 + x tx ) X⇤ y = A 1 X⇤ y A x x A X !#$%'(!)*+,                                            y                                                                                                            ⇥2 1
                                                                                                                                                                                p⇥
V =E                  (A                                                                                                                                                JO = x⇤ i 2 2 ⌃⌃
                                                                                                                                                                                              ⇥
                                                                                                                                                                                                 . a=   1              x⇤ ⇥ 2
                                                                                ⇤        1x ⇤                  ⇥             ⇤ ⇤ 1                                   a=
                                                  Figure 7: Decomposition of generalization error G into model error C, bias A variance V , where g denotes
                                                                     1 + x A 1 +2 A
      ⇥ D                ⇥
                                                                                                 x          1 x 1 + x B, and 2x                                                    (a T J1) ⇥i + x⌅ A⌅ A t1 x . ⇥i.+
                                                                                                                                                                                       ⇥                                  ⇥
                                                                                                                                                                                                                          1
                                                                                                                                                                                                                                i ⇥
                                                                                                                  ⌅        ⌅                                                        J+ T                       i=1x          x t 2
                                     1                                ⇥      yt ⌅ f⇥
                                               ⇤ optimal function, ⇤is a⌅⌅1 1function⇤i⇤ are the1 ⇤ functions from a slightly di erent training set.
                                                         1 J(⇥) f= learned yt+1 ⌅’s = 1 X                 learned t          t+1        , 1 ⇤                                i=1                                 ⇥
                                                                                                                                                                                                                      ⇥

     ⇤ =A 1 x y                A x x A 1 + x AA x x xx A X y A x x AJO X y
                                              1
                                                           xy                                      A x                       1        ⇤
                                                                                                                                                                             ⌅ m              xt ⇤X x ⌅        m
                                                                                                                                                                                              ⇥2 xt ⇤X x 1 ⇤p ⇥2 ⇤ 1 ⇥2 1 ⌅
                                                                                                                                                                                                        1=                ⌅
                                                                                                                                                                                                                                                              p

       t                           =A x6.2.1 Parameter Change-based 1 ⌅ 1
                                                    y                                                                                                                   = x⌅ A⌅x⇥xt1i  ⇤
                                                                                                                                                                                                                + a    x⇥ i x
                                                                                                                                                                                                                                     ⇥⇥i +i .
                                                                                                                                                                                                                                                  +
                                                                       1 +AL 1 + x⇤ At1 ⌅x items thata 1likely toainfluence thex the most.
                                                                                                                                                                                      1
                                   1 + x⇤ A 1 x                                   ⇤
                                                                               x(Settles et⇤al., 2008b) favors
                                                                                  1 A         x          t+1                   + x⇤ A 1 model                                  ⇥ x A xt ⇥i +
                                                                                                                                                                             i=1 ⇥                             i=1 i=m+1                                  i=m+
                                                            1 ⇤ changes A model’s parameters⇤ yfor the better, i.e. approach the optimal parameters, it
                                                                                   x x 1A x
                                                  Parameter Change-based                                                 are
                               ⇤ ⇤   1
                           1 + ) x xis then beneficial to select the + that A x are . 1 X⇤ y
                 (A + x x x A y11x Assuming x A⇤ 1 xin an itemA ⇤has the1greatest impact on the model’s parameters:
                                        A = A x x ⇤ t )21 x x x A
                                                     (y
                                                              thaty
                                                                                                                                                                                                                                                1
                                                                                                                                                                                                                                                  ⇤p
         =A 1 x y
                                                                                                                                                                    p
                                                     ⇥                   ⇤                                                                                       ⌃⌃      p          ⇥ ⇥⌅ ⇥ ⇥ 1 1
                       y      ⌅
                                   = = x⇤ ⌅
          J(⇥) = ⌅⌅t yt+1 ⌅1 + 1 X A ⇤1 x ⌅x
                                      2
                                                                  1 t+1
                                                                               . , G = (x )⇥ X A I,x , ⇤ = A 1 X⇤ y. ⌅ A⌅⌅t1=t = ⇥ x⌅ x⌅ xt x⌅
                                                                                     A 1 + = ⇤ + y Y1 T Tt⇥(x ,y)),
                                                                                     ⇥ change X x                                              x⇥ x A x 1
                                                                                                                                                         px (22)             ⇥ 1i               i
                                                                                                                                                                                                                                                        i=m+1
                                                                                                                                                                                                                                                               a
                                                + x tA                                           a          E    L(                        a
                                                                                                                                                a=
                                                                                                                                                    ⇥
                                                                                                                                                             x⇤i=1 i=1
                                                                                                                                                                ⇥     i
                                                                                                                                                                         2        ⇥    i       t ⇥i +i
                                                                                                                                                                                                         ⇥i +
                                      ⇤ I where T                                             ⇤ t+1                                                              ⌃m⇥ + ⇥
            A 1 q(x) x⇤ ⌅ t )⌅ parameterare the model’s parameters estimatedyfromanthe current training ⇥TtrainingTset T,y)and Li=1model’s m ⌃⌅i ⌅⇥ x⌅ ⌅⇥ p⇥ 1 1 + 1 1 p ⌃x⌅ ⌅⇥ x⌅ ⌅⇥ .
         p(x) ⇤=x (y                                          estimates after a hypothetical rating of
                                                                                                                               set , and ⇥(x
                                                                                                            item xa 0 added to the 1
                                                                                                                     is                        ,
                                                                                                                                                  are the      a

                                                                                                                                                        m the loss
                                                                                                                                                         is =
                                                                                                                                                                                                                            ⌃p                      ⇥
         =                ⇤      1x
                                         t . t+1 1
                                                  function that measures x y erences between the parameters. ⇤ y
                                                A xx A          ⇤       1 the di                1
                                                                                         A xx A X       ⇤        1
                                                                                                                                                ⌅=
                                                                                                                                                      ⌅           = ⇥2x⇥ x⇥ i t xti ⌅ + ⇤ +
                                                                                                                                                                                 1i         1 ⇥i ⇥ + ⇥ 2
                                                                                                                                                                                                     i                                  ⇥ xi
                                                                                                                                                                                                                                             ⇥     i t xt
                                                                                                                                                                                                                                                           i
                                                                                                                                                                                                                                                                i
 (x) ⇤= q(x) 1 + x =A 1 x y A
         ⇤           ⇤ A                                                                                                                                        ⇤
                                                                                        1                      ⇤⇤                                 t          x⇥ i=1 i=1                 +                  i x⇥     i i=m+1. i=m+1
                                                             x⇤ A= x A x 1(y ⇤ x 1 t ) .
                                                                                                                                                                      i
            t+1        t                                                1                                                                                                   ⇥i +
                                        ⇥
                                                 ⇤ 1 +Variance-based decomposed into + x A xmodel error C (the di erence between the opti-
                                                yt+1 approachtthe error is ⇥
                                                  6.2.2
                                                                ⇤
                                                                y          X             ⇤ t+1three (A 1 xx x ) (X y + x y )
                                                                                                   ⇤ components: ⇤1 1⇤ ⇤
                                                                                                                                                       i=1                                       i=m+1
                                                                                                                                                                                                                                      1
                                                                                                                                                                                                                                          ⇧p⇧
                                                                                                                                                                                                                                           1
                                                                                                                                                                                                                                             i=m+1 x⇥ x
                                                                                                                                                                                                                                                   p         ⌅
                                 = X X +x⇤function approximation Agiven1 + xAA x +the A function f ), bias B (the di erence between
                 ⇧ n ⇤ A 1 ⌅ 1 + malI, 1 x
                                                  In this
                                                        A                                          = 1 x
                                                                  ⌃ x⇤ g, 1 x current model, and ⇤ true X y
                                                                                        the                                                                                                                             1
                                                                                                                                                                                                                            ⇤p                 ⇤
                                                                                                                                                                                                                                                      ⇥2
                                                                                                                                                                                                                                                   i=m+1
                  ⌥ =A i )x y                          1 ⇥2⇤
                                                  the current approximation ⇥ ⇤ an                                                                                                                                             i=m+1 x⇥             i
     ⇧ n min               q(x                                                ⇤
                                                A 1 xIn(y A 1 x fhave:) optimal one g), and+ x AV⇤(how1much y + (A approximation f 1 x y .
                                                                          xwe andt                 = (A variance 1 x X⇤ the function + x x⇤ )
                                                                                                                 ⇤ x )
                                                                                                                                                                  ⇥

I          ⇤          ⌅                       ⇥ ⌃ ) + x words,
                                            f (xivaries ).yi  ,⇥ 1
                                                           0   other                                   1+x                                                                                                                              a
                   ⇤
       ⌥ q(xiyt+1 p(xi ) = X 2
                    )           ⇤
                               yt           ⇥                                          .            G = C + B + V.                                           (23)
                                                                                                                                                                                                         p
                                                                                                                                                                                                  1 ⌃⌃ ⌅ ⇥ ⇥⌅ ⇥ ⇥
                                                                                                                                                                                                               p
min
A                  i=1      f (xi1)x (yi
                             A          y        x t
                                                  One1⇤ ) x⇤ A 1 x
                                                         +                               ⌅t
                                                  , ⇤ solution (Cohn et al., 1996) is to minimize the variance component V of the error by assuming that the                x⌅ A⌅ A t1⇥t ⇥ 1
                                                                                                                                                                               ⇥ x
                                                                                                                                                                                    ⇥
                                                                                                                                                                                      1
                                                                                                                                                                                        x x                       x ⇥ x ⌅ xt x ⌅ , ,
                                                                                                                                                                                                                          ⇥
                                                                                                                                                                                                                           i
                                                                                                                                                                                                                               i       t
                                                                                                                                                                                                                                        i
                                                                                                                                                                                                                                             i
             p(xi ) =                            .
                                      bias component becomes negligible (if this assumption is not satisfied then this method may not be e ective).                i=m+1
                            J( ) = variance ⇤a number of⇥2
        i=1                                                                                                                                                           i=m+1
   ⇥ ⇤ ⇥ 1                1 + x⇤ A Theret+1 the model’smethods proposed that aimJOselect training inputs seeks to selectcertain measure points
                                      1 x are
                                         y              ⇤
                                      ⇥⇤ of yt parameters. The A-optimal design (Chan, 1981) for reducing a training input of the
                                                                                         to
                                                                                                                                                    JT                                                                                        JT JT
                                 ⇤     1 as
                                                                     ⇥2
   1J( ) = (y x⌅ ⇧ )2 x⌅ A 1 X⇥⌅ X⇥ A sox to minimize the average variance of the parameter estimates, the D-optimal design (John x⇤ A 1
                                                                                                                            A 1 x  Draper,
                                              y 0 x⇤ ⇤
                                      1975) seeks to maximize the di erential Shannon information content of the parameter estimates, and the
                    t         ⌅        2
                                         ⇤=                                     al., 2006)+ x tox⇤ ⇥ 1 = 1 1
                        (1 + x A 1 x )Transductive Experimentaltdesign (Yu et ⇤ (A 1seeks⇥⇤ )representative training points that may allow .
                                                                                                  find            A                   ⇤                 ⌃⌃                  ⇥2
          J( ) S= ⇥⇤t+1 yt ⇥2 0= retainingcomponent,1also 1= 1 ofaccount Aexistense of(x⇤model1inx(Sugiyama, 2006),+ x A to the JT JT
                                                                                                                                             1
             J     y         ⇤ = variance mostA the x (y into xxtesttpoints. X ALthe AAerror2component.1 in addition x
                             ⇤
                                                     of   information
                                                 ⇥ ⇤ ⇤ takes
                                                                          the ⇤ )
                                                                            ⇤               The    Xmethod
                                                                                                                 )
                                                                                                                   x.                                         x⌅ A⌅ A t1 xt ⇥2
                                                                                                                                                                ⇥ x
                                                                                                                                                                       1
                                                                                                                                                                         x
         = JR ,              yt+1 y⇥= X x A x
                             ⇤       ⇤t 1 +                                        the
                                                                                       .O =
                                                                                       J             ⇥         ⇥
                                                                                                                       ,                           xt ⇤X x
                                                                                                                                                                    ⇥
                                                                                                                                                                        J( | y = r)
             JP                           2 = 1 1 + x⇤ A 1 x
                                           ⇤ Image Restoration-based                          (1 + x⇤ A 1 x⇥ )2                                        xt ⇤X x
                               ⇤⇤                                                                                                                            ⇤                                      ⇤ d d              ⌅2 ⌅
                               y     x t
                                      6.2.3
                                                                         ⇤
                                                                                                        ⇥
                                                                                                                    ⇤                                 ⇥2
                                                                                    1 ⇥⇤problem of predicting the user’s preferences as one of image restoration1(Nakamura
                                                                                                ⇥    1                                                                                          ⌃⌃ 1 ⌃⌃         ⇥ ⇥⌅ ⇥ ⇥ 2
                       =           ⇤) , 1
                                  ⌅⇧ 2
                                                                     x A X XA x.
                                                              It is also possible to ⇤
                                                                                     treat the
                                                                               (x⇥ A x⇥ )   1  2
                                                                                                                              xt ⇥X x
                                                                                                                                          ⇤      1
                                                                                                                                              x⇥ A ⇤ xt                ⇤
                                                                                                                                                                   A xx A               1    ⇤
                                                                                                                                                                                            X y
                                                                                                                                                                                            ⇥ ⇥      1    x⌅ x⌅ xt x⌅     . .
                      JR = (y1 + x t A x
                                 x                                JO =                                ,          J⇤ of 1 ⇤
                                                               Abe, 1998), that is, based on our limited knowledge = a user’s preferences (a1
                                                                                                 (A + x x ) X y = A X y                                          .
                                                                                                                                                  partial picture), we try to restore
                                                                                      ⇤ user’s likes and dislikes.TThe AL task is+ x⇤ A 1 x )training points that would
                                                                                                                                                                                                           ⇥  i
                                                                                                                                                                                                              ⇥   i
                                                                                                                                                                                                                     i
                                                                                                                                                                                                                     t  i
                                                              the complete (1 + x the
                                                                            picture of A
                                                                                      ⇥
                                                                                             1 x )2
                                                                                                ⇥                               (1 then ⇥ select the 2
                                                                                                                                           to         ⇥             1 + x A 1x   ⇤            xt ⇤X x
                                                                                                                                                                                                  xt ⇤X x
                                                                                                                                                                                                              i=m+1
                                                                                                                                                                                                                 i=m+1  J( )                P (y = r)J(
                JS = x⌅ A 1 X⇥⌅ X⇥ A 1 x ,                    best allow us ⇤                                ⇥2
                                                                            to restore the “image” of the user’s preferences. It is interesting to note that this approach satisfies
                                                                                                ⇤       1                                                                                                                              r
                                                                       2
                                                              the desired properties of the ALx A outlined in Section 2. For example, if a point already exists in aJ
                                                                                               methods xt                                                                     region,
                                   J( ) = ⇥⇤
                                           y                    ⇤
                                                                y⇥              xt ⇥X x        ⇥                                                              JO            JT JT
                                                                                                                                                                               T            x⇥ x⇥                                                     X⌅X⌅
                                                                                                                                                                                                                                                        X
                    JP = (1 + x⌅ A 1 x )2 .t+1                     tT
                                                              thenJ = sampling neighboring points the image in that region could likely be restored. This approach also
                                                                   without                                       . ⇤                                                                                          ⇥
                                                                               ⇥            ⇤ edges of 2
                                                              may favor sampling close to the
                                                                                  (1 + x A                       X X
                                                                                                  1 x ) image components (decision boundaries).                                                              X  x⇥
                                                                                                                                                                                                                 ⇥
(Section III-A1). Size of the node reflects degree of the node (scaled logarithmically).



 Connecting People                                                          relation to number of alumni nodes differs. Stanford University
                                                                               has a significantly higher ratio of companies per alumni in
                                                                               leadership roles, followed by Harvard, trailed by Berkeley, and
                                                                                                                                                                                                         subdued edges in Figure 2. The distance from the universities
                                                                                                                                                                                                                                                      University Alumni


                                                                                                                                                                                                         to the cloud of ‘financial’ clusters also varies. In particular,
                                                                                                                                                                                                                                                          Stanford

                                                                                                                                                                                                                                                          MIT
                                                                                                                                                                                                         Stanford and Berkeley are rather close to the financialPerson
                                                                                                                                                                                                                                                                               Other Nodes

                                                                                                                                                                                                                                                                                    Financial Org.

                                                                                                                                                                                                                                                                                    Company
                                                                                                                                                                                                                                                                                       cloud.
                                                                                                                                                                                                                                                                                                     t
                                                                                                                                                                                                                                                                                                     t
                                                                                                                                                                                                                                                                                                     fi

 Collaboration Networks
                                                                                                                                                                                                                                                          Harvard


                                                                               MIT. A high ratio of company nodes indicates that alumni                                                                  This may be explained by the geographical proximity of these
                                                                                                                                                                                                                                                          Berkeley                  University       b
                                                                               have been involved with multiple companies - either through                                                               universities to one of the largest sources of venture funding –
                                                                                                                                                                                                                                                               Size (Centrality log-scaled)
                                                                                                                                                                                                                                                                                                     l
                                                                               employment, advisory or investment activities. In addition,                                                               Silicon Valley. While universities themselves are not embedded                              o
                                                                               the number of highly connected alumni (large nodes with                                                                   within the financial clusters, a noticeable proportion of alumni                             f
                                                                               many connections located on the perimeter) differs significantly                                                           are deeply connected within the financial clusters by having                                 N
                                                                                                                          University        Alumnus
                                                                               between universities (we further explore this in Section III-B).
                                                                                                                                                                Company
                                                                                                                                                                                                         direct or indirect relations with multiple financial organizations.                          a
                                                                               One particular characteristic of highlySize (degree log-scaled)
                                                                                                                              connected alumni stands                                                    Stanford has the largest number of alumni connected to the                                  a
                                                                               out, namely their collaboration patterns. Stanford’s densely                                                              financial cluster, followed by Harvard (even though university                               T
                                                                               connected alumni are highly likely to collaborate with fellow                                                             itself is relatively distant from the financial cluster); followed                           a
                                                                               alumni (indicated by the company nodes being pulled away                                                                  by Berkeley, and only a few alumni from MIT. The proximity                                  t
                                                                               from highly connected alumnus towards other less-connected                                                                between alumni and their alma matters appear to differ signif-                              l
                                                                               alumni in the center). In the networks of other universities, the                                                         icantly. Berkeley alumni tend to be clustered together, MIT to                              t
                                                                               collaboration of highly connected individuals with their fellow                                                           somewhat lesser degree, and Stanford and Harvard alumni are                                 N
                                                                               alumni is evidenced but to a lesser degree.                                                                               rather dispersed. Proximity between universities differs as well.
                                                                                  Harvard alumni appear active in leadership positions in                                                                Stanford and Berkeley are close together (many alumni hold                                  n
                                                                               technology-based startups, even more so than MIT alumni                                                                   leadership positions in the same companies). One of the likely                              v
                                                                               (Figure 1b vs. 1c). A possible explanation for the relatively                                                             explanations for this network proximity is the geographical                                 t
                                                                               lower level of MIT alumni may be attributable to the focus of                                                             proximity of both universities to Silicon Valley where many of                              b
        (a) Stanford University.                (b) Harvard University.                 (c) MIT.                           (d) UC Berkeley.
                                                                               this dataset on leadership positions in the organizations. While                                                          the investment firms and startup companies are located. Harvard                              S
                                                                                                                                                                                                       Figure 2: Inter-University NetworkasNetwork
                                                                                                                                                                                                         and MIT do not appear to have (between relations with other
                                                                                                                                                                                                                          Inter-University strong Stanford, Harvard,                                 p
Figure 1: Intra-University Networks. Networks of the above universities are expanded in a breadth first manner so in the depth
                                                                               engineers play a key role, they often do up to a technology
                                                                                                                                                                                                         universities in these settings.
                                                                                                                                                                                                       MIT, Berkeley) (Section III-A2). Network is obtained by start-                                U
of 2, (showing university, alumni and companies they are associateddevelopment capacity rather than in the leadership activities) that
                                                                                with through employment, investment or other positions
                                                                                                                                                                                                       ing with the nodes of the above mentioned universities and                                    t
(Section III-A1). Size of the node reflects degree of the node (scaledare visible in public relations communications. Some support
                                                                                logarithmically).
                                                                               for this explanation may be seen in the Figure 2 relatively large                                                       performing a breadth-first expansion up to the depth of 3.                                     p
                                                                               distance between Microsoft and University of Washington, even                                                                                                                                                         e
                                                                               though a large number of engineers atUniversity  Alumni Other Nodesindeed
                                                                                                                                     Microsoft are                                                                                                                                                   w
relation to number of alumni nodes differs. Stanford University
has a significantly higher ratio of companies per alumni in                     from University of Washington.                        Stanford                 Financial Org.
                                                                                                                                                                                                       level entities/nodes that are linked to previous levels including
                                                                                                                                     MIT
                                                                                  2) Inter-University Network: A graphic representation of
                                                                                                                                                              Company
                                                                                                                                                                                                       financial organizations, company employees, etc. Since we                                      B
leadership roles, followed by Harvard, trailed by Berkeley, and                                                                      Harvard                  Person


MIT. A high ratio of company nodes indicates that alumni                       the alumni-based inter-relations between Berkeley       universities, shown    University                               are primarily interested in relationships among alumni, all of
have been involved with multiple companies - either through                    in Figure 2, was produced as follows. Four universities were
                                                                                                                                         Size (Centrality log-scaled)
                                                                                                                                                                                                       other entities are faded out, except for the above mentioned                                  n
employment, advisory or investment activities. In addition,                    selected for analysis: Stanford University, University of Califor-                                                      universities and their alumni. In addition, we glimpse at the                                 o
                                                                               nia (Berkeley), Harvard University and Massachusetts Institute                                                          relations between alumni and investment firms (a very impor-                                   n
                                                                                                             Betweenness Centrality
                                                                                    Betweenness Centrality




the number of highly connected alumni (large nodes with
                          Betweenness Centrality
 Betweenness Centrality




many connections located on the perimeter) differs significantly                of Technology (MIT). From these nodes we have performed                                                                 tant factor for entrepreneurism). Therefore, nodes of financial                                l
between universities (we further explore this in Section III-B).               breadth-first expansion up to the depth of three: 1st level                                                              organizations are not faded out.                                                              q
One particular characteristic of highly connected alumni stands                being alumni of these corresponding universities, 2nd level                                                                Two distinct groups – universities (in the lower left corner)                              n
out, namely their collaboration patterns. Stanford’s densely                   are companies with which alumni have relations, and 3rd                                                                 and financials (in the upper right corner) – are visible in the                                S
connected alumni are highly likely to collaborate with fellow                                                                                                                                                                                                                                        1
alumni (indicated by the company nodes being pulled away                                                                                                                                                                                                                                             D
from highly connected alumnus towards other less-connected                                                                                                                                                                                                                                           p
alumni in the center). In the networks of other universities, the                                                                                                                                                                                                                                    i
collaboration of highly connected individuals with their fellow
alumni is evidenced but to a lesser degree.                                                                                                                                                                                                                                                          e
   Harvard alumni appear active in Alumni Indexleadership positions in
                                          Alumni Index                                                          Alumni IndexIndex
                                                                                                                    Alumni
                                                                                                                                                                                                            University                                                                               F
(a) (a) Betweenness Centrality Alumni Nodes in so Networks (University and (b) Betweenness Centrality Alumni Nodes in Networks (University andand
     Betweenness Centrality of of even more Networks (University and (b) Betweenness Centrality of of Alumni Nodes in Networks (University
technology-based disconnected).
                      startups,    Alumni Nodes in
                                                       than MIT alumni                                                                                                                                      Other Entities (Company, People, Financial Org.)                                         m
alumni nodes are are
    alumni nodes disconnected).                                          alumni nodes are are connected).
                                                                            alumni nodes connected).
(Figure 1b vs. 1c). A possible explanation for the relatively                                                                                                                                                  Size (Centrality degree log-scaled)
                                                                                                                                                                                                                                                                                                     t
Figurelevel of MIT alumni may be attributablealumni nodes thethe network (connected thethe university node (b)), and (disconnected
    Figure Betweenness Centrality (y-axis) of alumnithe focus of network (connected to to university node (b)), and (disconnected
lower   4: 4: Betweenness Centrality (y-axis) of to nodes in in                                                                                                                                                                                                                                      t
                                                                                                                                                                                                                    University-Company Network
                                                                                                                                                                                                         Figure 3: Universities within the Business Network (partial                                 c
this dataset on leadership positions The x-axis corresponds to alumni ordered in descending order of centrality for each of the
from thethe university node (a)). inx-axis corresponds While
    from university node (a)). The the organizations. to alumni ordered in descending order of centrality for each of the
—
                                                                                                                —        —-
                                                                                                                Generalized Assignment Problem
                                                                                                       —-
Connecting People  Contents                                                                                 —- Generalized Assignment maximize
                                                                                                       Generalized Assignment Problem p, choose a Problem
                                                                                                        —
                                                                                                                Objective: given a paper
                                                                                                                M given a Assignment Problem collectively possesses
                                                                                                                Generalized a fixed size s) that
                                                                                                       Objective: ⇥ M (ofpaper p,given a paper subject to a gro
                                                                                                        —- the most expertise about p: a groupa ofp, choose
                                                                                                                         Objective: choose
                                                                                                                Objective: given a paper p, choose group of experts
                                                                                                                                                                       group of experts
                                                                                                                                                                          experts
                                                                                                                                                                                          R(M

Expertise Finding  Group Formation                                                                 M ⇥ M (ofgiven ⇤papers) that fixed sizeof experts M ⇤ M
                                                                                                                         a fixed size (ofchoose a group possesses collecti
                                                                                                                         M a M p, a                   collectively s) that
                                                                                                        Objective:⇥ M (of a fixed size s) that collectively possesses
                                                                                                                M
                                                                                                    size s) most collectively possesses the most expertise about p:
                                                                                                       the that expertise about p:
                                                                                                                the most expertiseexpertise about P
                                                                                                                         the most about p:R(M, p) = p:
                                                                                                                                     maximize                               m2M r (m, p)
   Task Description                         Task Description
                                                                                               6'1'.%
                                                                                                                                                                      |M = R(M, p) ⌅=
                                                                                                                                                             P
                                                                                                                                      subject to
                                                                                                                           maximize R(M, p) = m2M r |(m,sp)             P
                                                                                                                                      maximize R(M, p) = m2M r (m, p) P
                                                                                                                                                               P
                                                                       !#$%'()*+*,-).(./)                              maximize R(M, p) |M | = s r R(M, p) =
                                                                                                                           subject to              maximize (m, p)
                                                                                                                                                          = m2M
                                                                              7%2*.*.1%                                                 Limitation X |M | = s
                                                                                                                                      subject to
                              Group
                                                                              896').*.1%
                                                                                                                            subject to              subject = s r (m, p) .
                                                                                                                                                           |M | to
                                                                                                                                           Expertise⌅=is not additive: |M |
                                                                                                                                              R(M, p)
                                                                                                                                                    X                m2M
                                                                                                        —       Limitation                 – R(M, p) ⌅= X p)r.(m, p) .
                                                                                                                                     R(M, p) ⌅=                 r (m,
                                                                                                        Training Set:— = (XT additive: iExpertiseT Estimation
                                                                                                                                                        m2M
                                                                             4'#')(5')%
                                                                                                                Expertise is not , YT ) = {(x , f (xi ))xi 2X }
                                                                                                       Limitation
                                                                                                                           T               Group                     m2M
                                                                                                                         Training (and = (XT , Y Y ): RT
                                                                                                        Function learned from XSet: Tcorresponding ) = {(xi , f (xi ))
                                                                                                                Limitation
                                                                                                                –                             —                                  b
                                                                              !#$%'#()*+,-.%         Expertise is not additive: TAssumptions T T
                                                                                                                                          bT ) = L(RT , f )
                                                                                                                                                       b
                                                                                                                Expertise is not additive:
                                                                                                        Generalization error: G(R ⇤
                                                                                                                Group FunctionEstimation from XT (and correspon
                                                                                                                          Expertise learned
                                                                              /'010%('2*(%++')3% –          –
                                                                                                                Assumptions                M—- athors of paper p; so
                                                                                                                                               p are
                                                                                                       Group Expertise Estimation Generalized Assignment Prob
                                                                                                                         Generalization error:T0, where =L(⌥ andf )    b             b ⇤
                                                                                                                                           R(M, p) R G(R ) =M1,RT , p =
 Researcher Profile    Researcher Profile   Researcher Profile
                                                                                                                Mp are Expertise EstimationG(= ) ⇤ T
                                                                                                                Group —
                                                                                                                    —                             min
                                                                                                       Assumptions athors of paper Xp; ⇤ so R(Mp , p)
                                                                                                                    ⇤                                       b                          M
                                                                                  (-.7)*:;7'%$.-='1'%
                                                                                                                R(M, p)of—- where M ⌥ R(M ⇤ ,Ø. given a paper p, c
                                                                                                                    —-
                                                                                                                Assumptions
                                                                                                                     —                        Objective: = 1, and
                                                                                                                                                    T
 Knows                                                                                                — p are athors
                                                                                                       M  ⇤                  = 0,
                                                                                                                                paper p; so         Mp = p)
                      Knows               Knows
                                                                                                        g: optimalare athors Assignmentp; so R(Mpa p) ⇤min G( b t
                                                                                                                    Generalized(in the ⇤
                                                                                                                    ⇤ function                sollution space) ⇤ ,
                                                                                                                                                      Problem
                                                                                                                                       of paper ⇥ p
                                                                                                       R(M, p) = 0, where M ⌥ MpM Ø. ⇤M (ofM ⌥Problem RT )
                                                                                                      —-
                                                                                                                Mp—-
                                                                                                                              GeneralizedR(M,=choose a fixed Tsize s)
                                                                                                                                                =                           Mp 1, R(M,
                                                                                                                                                                                =      and
                                                                                                        b learned function given aM ⌥ Assignment group. of experts
                                                                                                        R:      R(M, p) = 0, where paperProblem ⇤
                                                                                                                    Objective: Assignment pp, p) =
                                                                                                                     Generalized                    M         Ø.                 X
                                                                                                      Generalized Assignment Problem most ⌥ Mp Mp about p:
                                                                                                                                              the        M expertise⇤       ⇤
                                                                                                        b           M ⇥ M (of fixed size p, choose a⌥groupchoose a
                                                                                                                     Objective: given a slightly a paper Mp possesses
                                                                                                                              Objective: given di⇣erent training
                                                                                                        Ri ’s: learned functionsaR(M,paper s) that collectively of experts    p,
                                                                                                      Objective: given a paperfrom a p) = a group theexperts set.spac M
                                                                                                                                          p, function p) = of . sollution
                                                                                                                                              choose
                                                                                                                              optimal (of p: (in
                                                                                                                    the g: M use Learn R group expertise.
                                                                                                                B (ofV most expertise that collectivelycollectivelyestimate
                                                                                                                    + ⇥ and ⌘⇥ M abouta s)and⇤ size ⇤ to . possesses
                                                                                                        EG = Learn abfixed (of aitfixed sizeb fixed use its) that colle
                                                                                                                     M R C                 to
                                                                                                                                                  R(M, Mp
                                                                                                                          + M size s) estimate that possesses
                                                                                                      M ⇥ M   ⇣                                                          Mp
                                                                                                                          b expertise
                                                                                                      the = R R(x)useg(x) mostfunction aboutP
                                                                                                        B most expertise learned expertise
                                                                                                                                     2
                                                                                                       Learn    b and R: the estimate group expertise. maximize
                                                                                                                E bthe mostabout p: about p:
                                                                                                                —                          —                                 p:             R
                                                                                                                          b it to it to YT
                                                                                                                         R ’s:2 T = (XT , functions (x= P T
                                                                                                              ⇣ Training iSet: use maximize) =R(M, fp)expertise.}r (m, p)
                                                                                                                          b ⌘
                                                                                                                Learn R and learnedestimate{(xi , fromxia slightly di⌘
                                                                                                                                                             group i )) 2X
                                                                                                                                         maximize Set: p) = (X Y, Yto) = {
                                                                                                                                           Training P T subject T b
                                                                                                       —         b       b
                                                                                                                                                                              m2M
                                                                                                        V = R ER(x)
                                                                                                                Function = = B from X p) =R(M,i 2XT= | = T r (m, p)
                                                                                                                —
                                                                                                       Training Set: EG (XT , YsubjectTto, f (xicorresponding s T ): RT
                                                                                                                          T learned +)V {(xC =+
                                                                                                                           maximize T R(M, i(and ))x r|M m2M             (m, p)
                                                                                                                                                                          }
                                                                                                                           (x)) ⇣                       maximize R(M, p) =
                                                                                                                                                            ⌘ m2M
                                                                                                                Generalization X subject TT))= {(xR f (x )) R s X (and
                                                                                                                Training Set: = Function learned from
                                                                                                        C = (g(x) fsubjectTto T (XT , Ycorresponding iYTxi|2X T}
                                                                                                                                              G( b |M |2i ,
                                                                                                       Function learned from error: Challenge= T , f )|M): = T T b
                                                                                                                                           (andRto = L( b s
                                                                                                                                 2
                                                                                                                                                                                b
                                                                                                                                        b
                                                                                                                Function = ER(x) b b y corresponding G(): R) =
                                                                                                                    Challenge
                                                                                                        Use changes B the estimates Xyg(x)t+1 to to
                                                                                                                                         from T (and
                                                                                                                         in learned RT ) = L(RTsubject error: YTimprovem
                                                                                                                                         b Generalization estimate RT T |M
                                                                                                       Generalization error: G( additive: ,         t    bf ) 2                       b
                                                                                                      Challenge Generalization not
                                                                                                                    Expertise ⇣
                                                                                                                     Challengeis )
                                                                                                    generalization error G(x error: Expertise RT not additive:
                                                                                                                                               G(RT )⌘2 L( is ,bT))
                                                                                                                                                   b =    min b RG( f
                                                                                                                 b Expertise estimates b G(
                                                                                                                         V = b
                                                                                                        where y is are the isR additive: R ,T) was
                                                                                                                                      not
                                                                                                      Expertiset+1 not additive: ER(x) (xbTy )X added to the train
                                                                                                                                                           X
                                                                                                                                                after
                                                                                                                                                min
                                                                               !#!$%                                                            R(M, p) ⇤=G(RT ) r (m, p) X m
                                                                                                                g: optimal function (in XT number ofbtraining points is eq             .
                                                                                                                                                 the 2 min space)
                                                                                                        Gt : generalization error when the sollutionX
                                                                                                                         C =function p) f (x)),space) added. tor p) R(M, ps
                                                                                                                                                   X                    m2M
                                                                                                                 b                (g(x) sollution yp)Tr (m, m2M the ⌅= .
                                                                                                                                                  R(M, X ⇤= R(M, (m, training
                                                                                                       g: t+1 : R: –learned (in the after (x m2M is
                                                                                                                generalization error ⇤=
                                                                                                        G optimal function R(M,                               )          p)
                                                                                                                                                                                     p)
                                                                               !#$%'#()*+,-.%                                                                                             m2
                                                                                                        ⌅G = Ritoptimal :functiong:– in insollution space) (in the t+1
                                                                                                       R:
                                                                                                                                            (in the a
                                                                                                       b learned–functionchanges optimal functionerrortraining set
                                                                                                                 b Group Expertise Estimation estimates y
                                                                                                                g: ’s: learnedimprovement the slightly different
                                                                                                                 G       Use
                                                                                                                         Gt+1 functions from generalization bt                         y sollu
                                                                                                                                                                                        b
                                                                                                      –
                                                                                !#!$%                 —       EGGroup Limitation
                                                                                                                 b learned V +
                                                                                                                      =B        function Estimation
                                                                                                       Ri ’s: Expertise+ExpertiseR: slightlyExpertise Estimation
                                                                                                                R:Assumptions C b
                                                                                                                 b generalization⌘error G(x )
                                                                                                       b
                                                                                                      Grouplearned learned functions learned function
                                                                                                                       ⇣ functions from a                   different training set.
                                                                                                                    ’s: b ExpertiseGroupa slightly different training se
                                                                                                                RiM ⇤ are Estimation 2 is not additive:, p) = 1, and
                                                                                                                                                 from
                                                                                                                B= ECAssumptionsg(x)bpaper p; so R(Mp
                                                                                                       EG = B + Vp +R(x)⌘ y   athors of                                   ⇤
                                                                                                             ⇣ EG = B + V 2 C min G the ⇤estimates after (x y
                                                                                                                                              aret+1 M max ⌅G.
                                                                                                      Assumptions ⇤ where+bt+1 i ’s: learned functions from ,a s
                                                                                                                                           RAssumptions ⇤ , p) = 1, and
                                                                                                                     M⇣ are athors⌘2 x paper =p = R(Mp
                                                                                                                  b R(M,g(x) 0, where MR(M ⇤ , xp)Ø.
                                                                                                                            p) =          of        ⌃ p; so
                                                                                                       B ⇤ are R(x)p bof – generalization perror = 1, and⇤ numbe
                                                                                                      Mp= EathorsGb : paper p;⌘2 ⇤            so
                                                                                                                V = RR(x)b 0, where Mare + = Ø.when M
                                                                                                                         E ⌘ R(x) EG p⇣ B ⇤ V + M ⌃ the
                                                                                                                B R(M, tp) = g(x) ⇤ M= ⌃ MpathorsC of ⌘ p
                                                                                                                               E                                                paper p;
                                                                                                      R(M,⇣p) = 0, where M ⌃⌘ Expertise Estimation 2 .
                                                                                                               b = (g(x)Group 22 p R(M, b = 0, where (x , yM ⇤
                                                                                                                                2        M = Ø. R(M, p) =
                                                                                                                       ⇣Gt+1 : generalization error M ⌃⇤M ⇤ ⌃ ) is
                                                                                                                C       b
                                                                                                       V = R ER(x) f (x)) B = ER(x) ⇤ g(x) p             p)               after M
                                                                                                                                                                            Mp
                                                                                                                V = R Assumptions R(M, p) p
                                                                                                                          b ER(x)  b                     M ⌃ M=                              p
                                                                                                       C = (g(x) changes in the
                                                                                                                Use f (x)) ⇤          Gt estimates improvement in. genera
                                                                                                                         ⌅G2 = ⌅G2=JGt+1 : ↵bt ⇤ yt+1 ↵2 Mp estimate imp
                                                                                                                                        R(M, + Kp)⇣ = y             b   . ⌘ to⇤
                                                                                                                C Learn R and use it to estimate2paperexpertise. R(Mp
                                                                                                                    = (g(x)Mp (x)) athorsb ofMgroup 2 so R(M
                                                                                                                             b f are                                                          ⇤
                                                                                                                         — b semantic and structural to                      p;
                                                                                                       Use generalization error G(x )= t Rt+1 ER(x) 2 ⇤ improveme
                                                                                                                                                                p
                                                                                                             changes in the estimates yy yyt+1 ↵ b estimate
                                                                                                                                           = ↵b                 2
                                                                                                                                        J V bt b b
                                                                                                                    Use b R(M, estimates y
                                                                                                                          both                                       features.
                                                                                                                  and yt+1 in Kp) =group ↵bt ⇤M y ↵ to = Ø.
                                                                                                   generalization error G(x ) the =2 y0, where(x t+1t+1was added to th
                                                                                                               bwhereuse R are the estimates after group⌥) Mpestimate imp
                                                                                                                     Learn and use it to estimate y , y expertise.
                                                                                                      Learn RUse changesto estimate b
                                                                                                                             it                           expertise. b
                                                                                                            generalization errorstructural(g(x) t , y f (x))2 ⌦ training point
                                                                                                                                                           y
                                                                                                                                                           b
                                                                                                                    Use ensemble predictive structural features.
                                                                                                                                                      model.
                                                                                                                     Use both semantic ) when the number of
                                                                                                                                        G(x and features.               b
                                                                                                               b semantic estimates = (x , y ) was added to the train
                                                                                                                                                  t+1
                                                                                                      Use both t : generalization error
                                                                                                                G
                                                                                                       where yt+1 are theand               C after
                                                                                                                where yt+1 are predictive model. , y , yis) was added max
                                                                                                                    — b
                                                                                                                     Use ensemble             Learn b in ) xR(M, = is tra
                                                                                                      Use ensemble predictivethe Use changes (x training t+1estimat
                                                                                                                                           estimates after             min G              to M
                                                                                                                                                                                             th
                                                                                                       Gt : generalization error model.the after (x of useadded to the x ↵
                                                                                                        —- Gt+1 : generalization error Y )R and, fthe it to p) = equ
                                                                                                                                        when          number                      points
                                                                                                                                                                               estimates
                                                                                                                GtTraining Set: T = (XTwhen =in numberi ))xi 2XTerror
                                                                                                                    :— Gt Gt+1 : improvement {(xi ⇤(x of training point
                                                                                                                ⇤G generalization true output the semanticnot training se
                                                                                                                      = sinceerror error (xboth is generalizationaccessible.
                                                                                                                                                   , T                               }
                                                                                                                     Training Set: T fromTX T (and{(xy, f (x ))xand }struct
                                                                                                                                              Use , y valuesiy) isto 2X
                                                                                                      —t+1 :: generalization the after                      )
                                                               #$'()(*+,'%),!#!$%
                                                                                                       G⌅G estimate
                                                                                                                                     generalization(x addedare the Y
                                                                                                                G Function learned= error, Yf (x= error } added to ): RT
                                                                                                                                              (X         )                G(x i )
                                                                                                      Training Set:Ggeneralization= {(xi afteri ))xcorresponding T T the tra
                                                                                                                       :
                                                                                                       ⇤G = Gtt+1 T =: (XT ,⇤YT ) Use ,Tgeneralization ierror
                                                                                                                                                                   ,
                                                                                                                                improvement inensemble Tpredictive mode
                                                                                                                                                                                           b
                                                                                                                          t+1                                     i 2X
                                                                                                                                                                                           b
Connecting
Models



Operationalization
of complex 
conceptual models

Motivation
Internalization




                        hFp://cmap.ccdmd.qc.ca/rid=1225215801935_1377957481_826/	
  
Model Diversity

                                           Table 10.1. Motivation Terms: Author by Factor Matrix
Author           Wlodkowski Paulsena      Donald   Keller   MacKinnon Panitz   Feldmanb Nuhfer   Farmer Theallc   Pintrich   Forsythd        Chickeringe
Factor
Inclusion             X                                                 X                                  X                      X                X
Community                                   X                  X                  X                                                                X
Climate                                                                           X                X
Ownership                         X                            X                  X       X        X                                               X

Attitude              X           X         X                           X
Affect                                                                                                               X
Interest                                                                                                   X                                       X
Awareness                                   X                                             X
Attention                                            X
Enthusiasm                                                                                X

Meaning               X                     X
Relevance                         X                  X         X                                           X                                       X
Value                                                                                                      X         X            X                X
Competence            X           X                                                                                               X
Empowerment                                                    X        X                                                         X
Confidence                        X                  X
Expectancy                                  X                                                              X         X
Leadership                                                                        X                X
High expectations                                                       X                                  X                                       X
Structure                                   X                                             X                X                      X                X
Feedback                                                                          X                        X                                       X
Support                                                                           X       X                X
Satisfaction                                         X                  X
Rewards                                                                                            X                              X
a   Paulsen and Feldman (Chapter Two).
                                                                                                                      (Theall	
  	
  Franklin,	
  1999)	
  
b Feldman and Paulsen (Chapter Seven).
c Theall, Birdsall, and Franklin, 1997.

d   Forsyth and McMillan, 1991.
Complex Modeling


                Typical Approach



                                                              Feature
                                     Extractors   Features                    Sub-Models     Sub-Models        Aggregation
                                                             Selection
                                   Conceptual                                 Conceptual

                   motivation      relatedness                                Expct Val T     Expct Val T
Text (tweets)
                     label                                                                                         A1
.………………                            sentiment                                  Cogn Diss T    Cogn Diss T
                                       ...                                        ...
.………………                                                                                                            A2

.………………                              Textual                                                                                  Classifier
                                                                             Computational

.………………                            part of spch                                   M1             M1                A3

.………………                            dependency                                     M2                               A4
                                                                                                 M2
                                       ...                                        ...

 Dataset Construction                Feature Extraction                  Sub-Modeling                     Ensemble Construction
Summary
                                                                  ---------
                                                                  ---------
                                                                  ---------
                                                                  ---------
                                                                  ---------



                                   AI                                                                                                                          ---------
                                                                                     ---------                                                                 ---------
                                                                                     ---------                                                                 ---------
                                                                                     ---------                                                                 ---------
                                                                                     ---------                                                                 ---------
                                                                                     ---------




Networks	
  are	
  crucial	
  for	
  learning	
  

•  use	
  AI	
  methods	
  to	
  construct	
  /	
  opTmize	
  networks	
  
    –  connecTng	
  contents	
  
    –  connecTng	
  people	
                                             Concept
                                                                        Extraction
                                                                                                  concept
                                                                                                   concept
                                                                                                     concept
                                                                                                      concept
                                                                                                                 concept
                                                                                                                  concept


                                                                                                            concepts
                                                                                                                    concept
                                                                                                                     concept
                                                                                                                                                                      Group Formation
                                            documents




    –  connecTng	
  people	
  	
  contents	
                                                                                                       tasks




    –  connecTng	
  models	
                          context
                                                    (documents)
                                                                                      Semantic
                                                                                      Mapping
                                                                                                                  concept


                                                                                                                  concept
                                                                                                                               concept


                                                                                                                               concept
                                                                                                                                                                       Influence
                                                                                                                                                                       Estimation
                                      concept       concept
                                       concept       concept                                                      concept      concept
                                         concept       concept
                                          concept       concept
                                                                                                                                             interaction log
                                              concepts




                                                                                                                concept            concept


                                                                                Knowledge Level                 concept            concept
                                                                                  Estimation
                                        concept        concept
                                         concept        concept
                                           concept        concept
                                            concept        concept                                              concept            concept

                                                concepts

More Related Content

PDF
Social Intelligence Systems for Wicked Problems
PPTX
Network of Excellence in Internet Science (Multidisciplinarity and its Implic...
PPTX
Conole keynote greenwich_draft
PPTX
Through a black mirror, palely
PPSX
Engage 2013 at SXSWedu, Nada Dabbagh PhD, Strategically Designed Personal Lea...
PPTX
PPTX
Conole salamanca final
PPTX
Emerging Pedagogies, Learning Spaces and Communities
Social Intelligence Systems for Wicked Problems
Network of Excellence in Internet Science (Multidisciplinarity and its Implic...
Conole keynote greenwich_draft
Through a black mirror, palely
Engage 2013 at SXSWedu, Nada Dabbagh PhD, Strategically Designed Personal Lea...
Conole salamanca final
Emerging Pedagogies, Learning Spaces and Communities

What's hot (20)

PPTX
Confounding redundancy: LMS, Social Networks & E-portfolio Systems - Moodlemo...
PDF
Teach Less Learn More
PPTX
Digital learning; connected, collaborated and constructed
PPTX
Structure for Collective Intelligent Organizations2
PDF
Knowledge Based Norway-10-6-10-mg russell
PPTX
Academics' online presence - assessing & shaping visibility 2012
KEY
Conole srhe
PPT
Teaching Crowds
PDF
Structure for Collective Intelligent Organizations
PPTX
Knowledge management manifesto_mkwi2012_20120301
PPTX
Virtual management
PPTX
Eveleigh ihr-2012
PDF
Awareness on web 2.0 technology in education
PDF
Escaping the age of speed: New Paradigms of Learning as Impacted by Social Te...
PDF
A Stage-Based Model of Personal Informatics Systems (Handout)
PPT
TEL Developments & Trends
KEY
Conole estonia
PDF
elearning 2.0 open social learningeng
PDF
Creating Knowledge Communities (2011)
Confounding redundancy: LMS, Social Networks & E-portfolio Systems - Moodlemo...
Teach Less Learn More
Digital learning; connected, collaborated and constructed
Structure for Collective Intelligent Organizations2
Knowledge Based Norway-10-6-10-mg russell
Academics' online presence - assessing & shaping visibility 2012
Conole srhe
Teaching Crowds
Structure for Collective Intelligent Organizations
Knowledge management manifesto_mkwi2012_20120301
Virtual management
Eveleigh ihr-2012
Awareness on web 2.0 technology in education
Escaping the age of speed: New Paradigms of Learning as Impacted by Social Te...
A Stage-Based Model of Personal Informatics Systems (Handout)
TEL Developments & Trends
Conole estonia
elearning 2.0 open social learningeng
Creating Knowledge Communities (2011)
Ad

Viewers also liked (20)

PDF
Aula06 matriz em C
PPTX
O papel da internet na Assessoria de Imprensa
PDF
IBECC - Contratos Empresariais - Revisão e Controle
PDF
Plano do Projeto
PDF
Ruby on rails - CEFET de Lagarto
PDF
Web 2.0 Collaboration – Using digital tools for redesigning governance
PDF
Implementacao e desempenho da virtualizacao no dcomp ufs
PPTX
Análise dos sites dos presidenciáveis - Eleições 2014
PPTX
Palestra - Bem vindo a era pós-digital: Empreendendo em um ambiente mutante.
PDF
Desafios da Cocriação
PDF
ThingTank @ MIT-Skoltech Innovation Symposium 2014
PPTX
Introdução ao scrum
PPT
Seminario - Versão Final
PPTX
MySQL - copiando, movendo e restaurando dados
PPTX
História do Escritório Virtual de Aracaju
PDF
Social Web Studies - What kind of collaboration is right for your business
PDF
Ecossistemas de startups nordestinos os desafios para a competitividade (2)
PDF
Web 2.0 Collaboration – Using digital tools for redesigning governance
PPTX
Projeto software alem da tecnologia v2
PDF
Apresentação ForkInSergipe
Aula06 matriz em C
O papel da internet na Assessoria de Imprensa
IBECC - Contratos Empresariais - Revisão e Controle
Plano do Projeto
Ruby on rails - CEFET de Lagarto
Web 2.0 Collaboration – Using digital tools for redesigning governance
Implementacao e desempenho da virtualizacao no dcomp ufs
Análise dos sites dos presidenciáveis - Eleições 2014
Palestra - Bem vindo a era pós-digital: Empreendendo em um ambiente mutante.
Desafios da Cocriação
ThingTank @ MIT-Skoltech Innovation Symposium 2014
Introdução ao scrum
Seminario - Versão Final
MySQL - copiando, movendo e restaurando dados
História do Escritório Virtual de Aracaju
Social Web Studies - What kind of collaboration is right for your business
Ecossistemas de startups nordestinos os desafios para a competitividade (2)
Web 2.0 Collaboration – Using digital tools for redesigning governance
Projeto software alem da tecnologia v2
Apresentação ForkInSergipe
Ad

Similar to Network Learning: AI-driven Connectivist Framework for E-Learning 3.0 (20)

PDF
Learning Networks: e-Learning 3.0
PPTX
Learningmatrix learning theories
PPTX
E-learning talk
KEY
Uwc connectivism seminar 22 aug2012-keynote
PPT
Arab Open University - Kuwait presentation
KEY
Distance Learning: the 4th Generation
PDF
Technologies For Higher Education
PPT
Hub DE summit Sydney
KEY
Conole
PDF
Hacking education
PDF
New Learning Paradigms and Technologies
PPTX
Beyond LMS Keynote to Canada Moodlemoot 2009
PPTX
Paredes chung lak12 v4.0
PDF
A Learning Framework for the Digital Age
PDF
Framework for online learning
PDF
Framework for Online Learning
KEY
Conole srhe
PPT
Iodl & icem 2010
PPTX
Modelling Learning & Performance: A Social Networks Perspective
Learning Networks: e-Learning 3.0
Learningmatrix learning theories
E-learning talk
Uwc connectivism seminar 22 aug2012-keynote
Arab Open University - Kuwait presentation
Distance Learning: the 4th Generation
Technologies For Higher Education
Hub DE summit Sydney
Conole
Hacking education
New Learning Paradigms and Technologies
Beyond LMS Keynote to Canada Moodlemoot 2009
Paredes chung lak12 v4.0
A Learning Framework for the Digital Age
Framework for online learning
Framework for Online Learning
Conole srhe
Iodl & icem 2010
Modelling Learning & Performance: A Social Networks Perspective

More from Neil Rubens (14)

PDF
Autism: Survey of Emerging Approaches [Clinical]
PDF
Collaborative Robotics (CoBot): Opportunities for Corporations
PDF
Autism: Survey of Emerging Approaches [Startups]
PDF
Solving the AL Chicken-and-Egg Corpus and Model Problem
PDF
Recommender Systems and Active Learning (for Startups)
PDF
e-learning 3.0 and AI
KEY
Active Learning in Recommender Systems
PPTX
Inconsistent Outliers
PDF
Outliers and Inconsistency
PPTX
Alumni Network Analysis
PPTX
Value Co-Creation in Innovation Ecosystems (Presentation @ Tokyo Institute of...
PPTX
Value Co-Creation in Innovation Ecosystems (English)
PPTX
Value Co-Creation in Innovation Ecosystems (Chinese)
PPTX
Japan Mobile
Autism: Survey of Emerging Approaches [Clinical]
Collaborative Robotics (CoBot): Opportunities for Corporations
Autism: Survey of Emerging Approaches [Startups]
Solving the AL Chicken-and-Egg Corpus and Model Problem
Recommender Systems and Active Learning (for Startups)
e-learning 3.0 and AI
Active Learning in Recommender Systems
Inconsistent Outliers
Outliers and Inconsistency
Alumni Network Analysis
Value Co-Creation in Innovation Ecosystems (Presentation @ Tokyo Institute of...
Value Co-Creation in Innovation Ecosystems (English)
Value Co-Creation in Innovation Ecosystems (Chinese)
Japan Mobile

Recently uploaded (20)

PDF
Complications of Minimal Access Surgery at WLH
PPTX
Renaissance Architecture: A Journey from Faith to Humanism
PDF
102 student loan defaulters named and shamed – Is someone you know on the list?
PDF
O5-L3 Freight Transport Ops (International) V1.pdf
PDF
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH 9 GLOBAL SUCCESS - CẢ NĂM - BÁM SÁT FORM Đ...
PPTX
BOWEL ELIMINATION FACTORS AFFECTING AND TYPES
PPTX
Introduction_to_Human_Anatomy_and_Physiology_for_B.Pharm.pptx
PDF
Saundersa Comprehensive Review for the NCLEX-RN Examination.pdf
PPTX
PPH.pptx obstetrics and gynecology in nursing
PDF
Business Ethics Teaching Materials for college
PDF
Mark Klimek Lecture Notes_240423 revision books _173037.pdf
PDF
Physiotherapy_for_Respiratory_and_Cardiac_Problems WEBBER.pdf
PDF
Classroom Observation Tools for Teachers
PDF
Microbial disease of the cardiovascular and lymphatic systems
PDF
Supply Chain Operations Speaking Notes -ICLT Program
PDF
Abdominal Access Techniques with Prof. Dr. R K Mishra
PDF
Basic Mud Logging Guide for educational purpose
PPTX
school management -TNTEU- B.Ed., Semester II Unit 1.pptx
PDF
3rd Neelam Sanjeevareddy Memorial Lecture.pdf
PPTX
IMMUNITY IMMUNITY refers to protection against infection, and the immune syst...
Complications of Minimal Access Surgery at WLH
Renaissance Architecture: A Journey from Faith to Humanism
102 student loan defaulters named and shamed – Is someone you know on the list?
O5-L3 Freight Transport Ops (International) V1.pdf
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH 9 GLOBAL SUCCESS - CẢ NĂM - BÁM SÁT FORM Đ...
BOWEL ELIMINATION FACTORS AFFECTING AND TYPES
Introduction_to_Human_Anatomy_and_Physiology_for_B.Pharm.pptx
Saundersa Comprehensive Review for the NCLEX-RN Examination.pdf
PPH.pptx obstetrics and gynecology in nursing
Business Ethics Teaching Materials for college
Mark Klimek Lecture Notes_240423 revision books _173037.pdf
Physiotherapy_for_Respiratory_and_Cardiac_Problems WEBBER.pdf
Classroom Observation Tools for Teachers
Microbial disease of the cardiovascular and lymphatic systems
Supply Chain Operations Speaking Notes -ICLT Program
Abdominal Access Techniques with Prof. Dr. R K Mishra
Basic Mud Logging Guide for educational purpose
school management -TNTEU- B.Ed., Semester II Unit 1.pptx
3rd Neelam Sanjeevareddy Memorial Lecture.pdf
IMMUNITY IMMUNITY refers to protection against infection, and the immune syst...

Network Learning: AI-driven Connectivist Framework for E-Learning 3.0

  • 1. 国立大学法人   電気通信大学   振興調整費   Unique and Exciting Campus   ネットワーク ラーニング Network Learning AI-driven Connectivist Framework for E-Learning 3.0   Neil Rubens Active Intelligence Group Knowledge Systems Laboratory University of Electro-Communications Tokyo, Japan
  • 2. Evolution of eLearning: eLearning 1.0 eLearning uses technology to enhance Learning --------- ‣ eLearning 1.0: --------- --------- --------- --------- ‣ reading: content became easily accessible ‣ logging: user’s activities could be logged and analyzed ‣ Learning Theories: ‣ Behaviorism: learning is manifested by a change in behavior, environment shapes behavior, contiguity ‣ Cognitivism: how human memory works to promote learning
  • 3. Evolution of eLearning: eLearning 2.0 ‣ eLearning 2.0: --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- ‣ writing: anybody can easily create content (e.g. blogs, wiki, etc.) ‣ socializing: interaction is easy (e.g. facebook, twitter, etc.) ‣ Learning Theories: ‣ Constructivism: constructing one's own knowledge from one's own experiences (enabled through writing) ‣ Social Learning: people learn from one another (enabled through socializing)
  • 6. Broken Knowledge Cycle ‣ Problem: The current cycle of knowledge creation/utilization is inefficient ! ‣ large portion of created content is never utilized by others* only 0.05% of twitter messages attracts attention (Wu et. al., 2011) only 3% of users look beyond top 3 search results (Infolosopher, 2011) ‣ large parts of created contents are redundant (Drost, 2011) ‣ Peak Social – the point at which we can gain no new advantage from social activity (Siemens 2011) utilize U0lized dge no wle K is ting Ex Redundant create Knowledge Novel *there are some personal benefits e.g. externalization, crystallization, etc.
  • 8. Information Overload for Computers not a Problem but an Opportunity Tan,  Steinbach,  Kumar;  2004   500  Points   2,000  points   8,000  points  
  • 9. Messaging Networks How can we use computers to learn in these settings? http://datamining.typepad.com/photos/uncategorized/2007/04/08/twitter20070405.png Citation Network Social Network hp://wiki.ubc.ca/images/f/ff/SocialWeb.jpg9 hp://www.kieranhealy.org/files/misc/SocCoreCites.jpg:
  • 10. Our  Focus   informa0on  connec0vity   Nova  Spivack©   social  connec0vity  
  • 11. Connectivism (Learning Theory) Connec0vism:  Knowledge  is  distributed  across  a  network  of   connecTons,  and  therefore  learning  consists  of  the  ability  to   construct  and  traverse  these  networks    (Siemens    Downes,  2008)   Property Behaviourism Cognitivism Constructivism Humanism Connectivism Learning Thorndike, Pavlov, Watson, Koffka, Kohler, Lewin, Piaget, Maslow, Siemens, Downes theorists Guthrie, Hull, Tolman, Skinner Piaget, Ausubel, Vygotsky Rogers Bruner, Gagne How learning Black box—observable Structured, Social, meaning Reflection on Distributed within a network, social, occurs behaviour main focus computational created by each personal technologically enhanced, learner experience recognizing and interpreting (personal) patterns Influencing Nature of reward, punishment, Existing schema, Engagement, Motivation, Diversity of network, strength of factors stimuli previous experiences participation, experiences, ties, context of occurrence social, cultural relationships Role of Memory is the hardwiring of Encoding, storage, Prior knowledge Holds changing Adaptive patterns, representative memory repeated experiences—where retrieval remixed to concept of self of current state, existing in reward and punishment are current context networks most influential How transfer Stimulus, response Duplicating knowledge Socialization Facilitation, Connecting to (adding) nodes and occurs constructs of “knower” openness growing the network (social/ conceptual/biological) Types of Task-based learning Reasoning, clear Social, vague Self-directed Complex learning, rapid changing learning best objectives, problem (“ill defined”) core, diverse knowledge sources explained solving
  • 12. ConnecTvism:   Nice  Theory   Need:   Tools    Frameworks   To  make  it  Prac0cal   hFp://imgs.sfgate.com/c/pictures/2011/12/19/ba-­‐BRIDGE20_SFC0105724887.jpg  
  • 14. Conceptual Framework network Analysis Layer --------- --------- --------- --------- connections --------- AI --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- Aggregation Layer links use AI to: Linking Layer §  connect contents §  connect people nodes §  connect people contents §  connect models Extraction Layer documents
  • 15. Modules Concept concept concept Extraction concept concept concept concept concept concept concepts Group Formation documents tasks concept concept context (documents) Semantic concept concept Influence Mapping Estimation concept concept concept concept concept concept concept concept concept concept interaction log concepts network Analysis Layer concept concept connections Aggregation Layer Knowledge Level concept concept Estimation links concept concept concept concept concept concept concept concept concept concept Linking Layer nodes concepts Extraction Layer documents
  • 16. Analysis Layer Link Layer Module Pipeline docs want to learn about: concept Search Engine (Example) Concept concept concept docs Extractor concept concept concept concept concept concept concept concept concept concept Semantic concept concept concept concept concept concept Mapping concept concept concept concept concept concept concept concept Search Engine concept concept concept concept … discussions … concept … concept … concept … concept concept
  • 17. Sequence Diagram (Example) user system user system user system I want to know about term t_i I think t_i and t_k are similar .. I want to know about term t_i and t_k social semantics semantics t_i t_i u_i: I think t_i is same as t_j … t_i t_i u_j: no t_is is more like t_p ... u_j: no t_is is more like t_p ... t_i t_i t_i t_i u_m: I think t_i and t_k are similar .. u_i: you are right t_i t_i t_i t_i t_i semantics t_i t_i contents contents t_i t_i t_i t_i contents t_i social social social u_i: I think t_i is same as t_j … u_i: I think t_i is same as t_j … u_j: no t_is is more like t_p ... u_j: no t_is is more like t_p ... u_k: you are both wrong t_i is ... u_j: no t_is is more like t_p ... u_i: I think t_i is same as t_j … u_j: no t_is is more like t_p ... u_j: no t_is is more like t_p ... u_m: I think t_i and t_k are similar .. u_i: you are right
  • 18. Connecting Representations ⇤ V (d1 ) Semantic + Network ⇤ V (d2 ) ⇤ Type! Network (N)! Content (C)! Proposed Hybrid! V (d1 ) ⇤ V (d3 ) ⇤ V (d2 ) Characteristics! This is a Title of a ! tfi,j = P ni,j Research Paper ⇤ (d V (d )1 ) V k nk,j Joe Fakeman Jane Noman ! 3 Analysis! V (d1 ) Nowhere University {fakeman, noman}@nowhereuni.edu |D| Abstract idfi = log ~~~~~~~~~~~~~~~~~~~~~ ni,j |{d : ti ⌅ d}| tfi,j = P !#$%$'()%*+(,( !#$%$'()%*+(-( ~~~~~~~~~~~~~~~~~~~~~ ! ~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~ k nk,j Introduction ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ V (d2 ) tf-idf i,j = tfi,j ⇥ idfi same as C part of N ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ |D| ⇤ ! V (d1 ) ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ idfi = log ! ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ V (d2 ) ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ |{d : ti ⌅ d}| w (d1 ) V = tf-idf i,j i,j User Interface! ! ⇤ V (d2 ) ./+$(/.(,( V (d3 ) This is a Title of a tf-idf i,j = tfi,j ⇥ idfi 2 3 Research Paper w1,j 6 w2,j 7 Joe Fakeman Jane Noman ! ⇤ ! 6 7 V (d3 ) V (dj ) = 6 . 7 Nowhere University wi,j = tf-idf i,j V (d ) 4 . 5 ⇤ {fakeman, noman}@nowhereuni.edu Abstract . V (d3 ) ~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~ 2 wt,j ~~~~~~~~~~~~~~~~~~~~~ 2 3 Introduction ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ 6 w1,j 7 ni,j Deployment! ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ⇤ 6 w2,j 7 tfi,j = P ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ V (dj ) = 6 . 7 4 . 5 ./+$(/.(,( ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ . ! k nk,j ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ wt,j V (d3 ) This is a Title of a ⇤ ⇤ |D| Research Paper V (di ) · V (dj ) idfi = log sim(di , dj ) = ⇤ ⇤ |{d : ti ⌅ d}| Joe Fakeman Jane Noman Nowhere University {fakeman, noman}@nowhereuni.edu V (di ) V (dj ) Execution
 Abstract ~~~~~~~~~~~~~~~~~~~~~ ⇤ Speed! ./+$(/.(,( V (d1 ) tf-idf i,j = tfi,j ⇥ idfi ~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~ Introduction ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ⇤ V (d2 ) wi,j = tf-idf i,j ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~- ~~~~~~~~~~~~~~~~~~ Reverse could also be done: i.e. converting textual representation to a network one. ⇤ 2 3 term-space V (d3 ) 6 w1,j 7 1 ⇤ 6 w2,j 7 V (dj ) = 6 . 7 . tfi,j = n P i,j 4 . 5 ⇥ ! k nk,j w|T |,j w1,j V (d1 ) ⇧ ⌃ 1 ! ⇤ ⇤ ⇧ w2,j ⌃ V (d1 ) |D| idfi = log sim(di , dj ) = V (di ) · V (dj ) ⇧ . . ⌃ ! |{d : ti ⌅ d}| ⇤ ⇤ V (di ) V (dj ) ⇧ . ⌃ V (d1 ) ! ⇧ ⌃ ! — V (d2 ) ⇧ w|T |,j ⌃ V (d1 ) —- ! Network Content based ⇥ idfi tf-idf i,j = tfi,j ⇥ ⇧ ⌃ V (d2 ) V (dj ) = ⇧ ⇧ ⌃ ⌃ ! wi,j i,j = (i, j) j) w = dist(i, ⇧ w1,j ⌃ V (d2 ) != wV (d tf-idf i,j ⇧ ⌃ ! —- i,j 3 ) 2 3 ⇧ w2,j ⌃ V (d2 ) Generalized Assignment Problem ! w1,j ⇧ ⌃ V (d3 ) 2 Objective: given a paper p, 1,j ⇤ 3 6 choose a 6 w2,jof 7 group 7 experts ⇧ . . ⌃ ! ! V (d1 ) w V (d ) = 6 M ⇥ M (of a fixed size6s) 2,j 7jcollectively (d ) ⇤ w that 4 ! possesses . . V 5 . 7 ⇤ . ⌅ V (d3 ) V (d ) = 6 6 7 1 ! the most expertise about p: . 7 j 4 . 5. w|N |,j w|N |,j V (d3 ) wt,j P maximize R(M, p) = m2M r (m, p) (1) ! subject to |M | =!(d ) s (2) V (d2 ) ⇤ ⇤ V (di ) · V (dj ) V 2 Challenge sim(di , dj ) = ⇤ ⇤ V (di ) V (dj ) Expertise is not additive: 1 ! X ! V (d3 ) R(M, p) ⇤= V (d3 . r (m, p)) (3) m2M – Group Expertise Estimation Assumptions Mp are athors of paper p; so R(Mp , p) = 1, and ⇤ ⇤ network-space R(M, p) = 0, where M ⌅ Mp = Ø. ⇤ term-network-space M ⌅ M⇤
  • 19. #pouf #noel #deco #mobilier #facebook Connecting Concepts #sustainable #evenementiel #savings #twitter #cadeau #reduce #buzz #design #reuse #money Modeling of: #inception #fuelcell #web #prop23 #hydrogen #recycle #cleantech #mobile #diy #new #florida •  topics #pr #innovation #california #news #global #home #biofuels #biofuel #greenroofs #publicrelations #boerse #asia #blog #thermal #frugal #biz #windenergy #aktien #hot #business #greenit •  lexicon #gossip #improvements #budget #cleanthinking #nw #change #construction #lightingdesign #warming #socent #benefits #finland #tudelft #eco #ff #green #audit #finance #ca #aia #doe #electric #cofely #scriptie •  semantics #duurzaam #architecture #health #india #efficient #greenbuilding #ecomonday #stock #footprint #renewableenergy #energy #tips #tip #carbon #ev #ecofriendly #ac #cancun •  dynamics #technology #homes #israel #china #greentip #climate #energyefficiency #delonghi #pv #solar #canada #co2 #csr #building #economist #alternative #education #btu #45 #dd45p #pt #dd50p #50 #science #re #cleanenergy #clean #electronics #cre #10000 #lg #art #africa #coal #dehumidifiers #novosti #climatechange #conservation #electricity #cooperative #emissions #edgestar #star #frigidaire #animals #nasa #environment #cop16 #efficiency #cville #datacenter #cdw #dehumidifier #rated #earth #dlr #pint #space #nature #sustainability #windpower #cars #65 #microwave #energysaving #it #70 #b #yahoo #sandiego #economy #soleus #c #renewables #greenenergy #oil #sd #peakoil #ontario #startup #dp1 #a #un #d #neweconomy #wef #encell #vc #dimmer #air #agw #water #gobeyondoil #wcs #pakistan #seattle #ecosmart #30 #sunpentown #globalwarming #unfccc #energyrevolution #iea #solarpower #ft #investment #us #uk #renewable #pkfloods #eecbg #platts #lamp #hybrid #011013 #epa #transport #solpwr10 #pentair #intelliflo #climategate #socialmedia #energystar #wind #products #led #vs #enviro #climaterealism #turbines #living #power #car #leaf #offshore #housing #sun #greenjobs #nissan #p2 #politics #cnet #google #career #meter #sunpower #utility #lighting #tech #london #greentech #tv #europe #dems #apple #organic #mass #topprog #gadgets #travel #greenliving #nuclear #eu #becktips #gadget #greenbuild #smartgrid #texas #dhilipsiva #baby #leed #cisco #rural #free #gop #tcot #obama #technews #tfb #taf #tcn #cloud #media #gridweek #gas #victoria #3 #fail #pledge #livewithless #glam #privacy #save #lx #streetlights #ftrs #p21 #careers #saving #r #hhrs #youcut #thepowerofwaiting #policy #leds #rs #winterhomeprep #football #veterans #smartmeter #ledstreetlights #ocra #lampe #windworks #ghg #sp1580 #momentive #motiongraphics #tlot #sgp #timelyadvice #win #underoath #licht #clothdiapers #arm #jobs #ebc #utilities #fuel #environmental #siemens #light #glennbeck #tpp #disambiguation #affiliate #linux #employment #hayward #2 #9 #twisters #reddit #hiring #46201 #912 #geospatial #marketing #fossil #teaparty #rulez #engineering #silver #6 #4 #heatpumps #heathrow #1 #capandtrade #gis #saveenergy #uksnow #job #digguser #fuels #realestate #pump #jobdanmark #in #digg #gold #sale #sp2610x15 #5 #8 #ontpoli #hohoho #mlfeeds #cdnprog #trhug #super #7 #stopglobalwarming #starbucks #architekt #cdnpoli #ondp #tweetmyjobs #calau #vt #cookies #aps #99 #indee #getinthegame #photography #indeed #credits #haier #pod #sfo #tax #esncm053e #management #jobangels #solarthermal #grid #meters #breakingnews #accenture #fb #smart #wpccc #dms #cochabamba #dsm #stocks #usa #cmpcc #noc #bolivia #cfd #mkt #webhosting #webhost #greenwebhosting Figure 7: Visualization (zoomable) of 416 Hashtags in Energy-Related Tweets, September 2010 Through January 2011; created with Network Explorer (Rubens et al., 2011). proaches that help understand the large scale conversations enhanced word-of-mouth to stimulate user-generated per-
  • 20. epilepsy differentiation Domain-specific therapy surgery migration atrial fibrillation glaucoma proliferation review mri smoking cytotoxicity p53 blood pressure Semantics echocardiography reactive oxygen species nutrition mitochondria hypertension gender apoptosis antioxidant diet oxidative stress insulin growth mutation diabetes physical activity infection metabolic syndrome 2 diabetes type metastasis sepsis insulin resistance radiotherapy complications phylogeny cytokines exercise refrontal cortex chemotherapy evolution stress body mass index inflammation lung cancer eeg fmri gene expression microarray anxiety cancer obesity metabolism depression atherosclerosis drinking water bangladesh ttention serotonin quality of life chronic obstructive pulmonary disease arsenic dopamine cardiovascular disease perspective multiple sclerosis schizophrenia breast cancer copd education outcome ethics laparoscopy immunohistochemistry internet fish adherence communication adolescents mercury pediatric prognosis asthma heart failure particulate matter lead trauma survival fertility myocardial infarction cadmium air pollution environmental health environmental exposure antibodies mortality pregnancy health korea children child occupational exposure climate change polymorphism adaptation polychlorinated biphenyls environment pesticides public health genetics prevention biomarkers exposure epidemiology biomonitoring incidence india hivrisk factors prevalence transmission dispatch outbreak brazil human africa zoonoses tuberculosis research surveillance china antimicrobial resistance letter viruses pneumonia management diagnosis molecular epidemiology bacteria treatment west nile virus drug resistance pcr osteoporosis parasites influenza elderly vaccine genotype malaria vaccination disease outbreaks
  • 21. P95-1032 P91-1022 W96-0201 Connection Formation J93-1006 W93-0301 P96-1018 P93-1001 P00-1050 P97-1039 P97-1038 P93-1002 P91-1023 P94-1012 A97-1050 C98-1066 A94-1006 J97-2004 J96-1001 Curriculum / Survey Design C94-2178 C98-2129 P97-1063 P93-1003 H91-1026 P93-1004 J93-1004 Original Design: W95-0115 P06-1062 J00-2004 C98-2153 W01-0505 P95-1033 W03-0301 H05-1011 Lacks Information P05-1057 J03-3002 W02-1012 C96-2141 P97-1037 W05-0812 J05-4003 P06-2014 P06-1065 P07-1001 J93-1003 P04-1066 H05-1010 N07-2022 C00-2163 P06-1097 D07-1006 W08-0409 N06-1014 J07-3002 P03-1012 P06-1009 H05-1012 N01-1026 C04-1006 P06-1002 J90-2002 J93-2003 C04-1032 N06-1013 H05-1022 P07-1039 Limited Diversity P03-1041 H05-1009 D09-1050 E06-1019 P07-1003 P08-1010 W07-0715 H01-1035 H94-1028 J04-2003 D07-1005 P09-3009 N06-1015 H05-1024 W03-1001 W07-0711 J03-1005 H05-1023 C04-1060 P05-1074 Limited Context W99-0604 W06-3123 D09-1040 P09-1104 N07-1061 N06-1003 W07-0403 C98-2225 D09-1141 A88-1019 W02-1018 D09-1106 P02-1050 W07-0709 P05-1059 N09-1013 P02-1039 P00-1056 J03-1002 P08-1012 N04-1021 D08-1033 W09-0435 W08-0306 J00-1004 P01-1030 W07-0401 P07-1108 P06-1067 P03-1019 D09-1105 W07-0716 P05-1032 J95-4004 W08-0307 W05-0909 P05-2016 P01-1067 W06-1609 E06-1005 N07-1008 N04-1033 P03-1011 J97-3002 W09-1114 H05-1095 W95-0107 E06-1032 D07-1038 C04-1073 N06-1004 W05-0634 W04-3207 D07-1030 W06-3108 N04-1030 P96-1023 J94-4004 P07-1020 P02-1038 C98-1013 P03-1002 W04-3212 D07-1007 P02-1040 C04-1030 D08-1066 P06-1146 W04-3250 W04-2412 H05-1098 C04-1090 P96-1021 W06-3114 C08-1064 W03-1008 P05-1072 W04-3228 N03-1021 N04-1023 W09-0809 D07-1055 N03-1017 P05-1069 N06-1002 W04-1513 W07-0718 W09-0426 W05-0620 W00-0726 J02-3001 W09-2310 D09-1136 W02-2018 H05-1101 P09-1106 P02-1031 J05-1004 W02-1039 W09-0434 D08-1011 J96-1002 P06-1091 P07-1005 D08-1089 N04-4026 D07-1062 P05-1073 J99-4005 W08-0302 W08-0304 W03-1006 W05-0908 J04-4002 W06-1668 P07-1091 W06-2303 J92-4003 H05-1021 P08-1115 J07-2003 W08-0403 C04-1204 W05-1509 P04-1083 E09-1061 P05-1066 W06-3106 P03-1021 P07-2045 P07-1040 N06-2026 N01-1025 P07-1090 E09-1033 W06-3104 W08-0308 E03-1071 I08-2087 C08-1137 D09-1123 P06-1098 N07-1070 I08-1066 P07-1002 P01-1017 W03-1013 W05-1511 H05-1099 P08-1009 P06-1096 N06-1031 D07-1091 D09-1114 W05-1514 P06-1123 D08-1010 D08-1060 W07-2208 N03-1028 D09-1037 H94-1020 H05-1078 P02-1036 C92-2066 N03-1033 A00-1031 E09-1049 J99-2004 P09-1036 W08-0401 N07-1029 C08-1050 N04-1032 W96-0213 W00-1320 H05-1059 W07-0405 D07-1056 W03-0401 N06-1032 C08-1041 P06-1088 W97-0302 W05-1507 N03-1016 P08-1024 A00-2031 D08-1076 P02-1043 J97-4005 P06-2101 N09-1029 P09-1066 P06-1066 W02-1002 D07-1080 W06-1619 P00-1058 J01-2004 N04-1014 J03-4003 D08-1012 W07-0702 N09-1025 D07-1077 W07-0701 P02-1034 J07-4004 C04-1041 P99-1069 J05-1003 P07-1120 N04-1022 D07-1104 P05-1033 P03-1046 N06-1040 D09-1023 D09-1073 P05-1039 W98-1115 W07-0706 P00-1061 W09-0103 D07-1003 W06-3119 N06-1019 P09-1042 D09-1021 D08-1065 D09-1008 W09-0424 N04-1013 P97-1003 W02-1001 C08-1127 P92-1017 N06-3004 W07-2202 C08-1144 W09-2306 P02-1035 N06-1033 W04-3215 P05-1011 D08-1008 A00-2018 W06-1628 P04-1014 D09-1119 D08-1024 J98-2004 H05-1036 D07-1079 P06-1077 P02-1042 P01-1010 P09-1103 W05-1515 N06-1024 J07-3004 N03-1014 N06-1022 W06-1608 W08-0402 P05-1034 W04-2003 P95-1037 P99-1059 N09-1027 D09-1108 P06-1121 E09-1044 P07-1032 W07-1202 P08-1037 J93-2004 W00-1201 W06-1666 P09-1087 P08-1025 P09-1020 N09-1049 H05-1064 N04-1035 W06-1638 W03-1005 P03-1056 D08-1093 J99-4004 D07-1078 P03-2041 N07-1063 P04-1041 P07-1089 P01-1042 W97-0301 J98-4004 W06-1615 P03-1054 P96-1024 C08-1138 P08-1114 P09-1065 P96-1025 P05-1038 W04-3224 W06-3601 D09-1135 E09-1090 P02-1018 P04-1015 D09-1059 D09-1127 P04-1042 W06-2904 D07-1027 H91-1060 P08-1066 C02-1126 W09-1008 N09-1026 P08-1064 I05-1007 P05-1023 W07-2219 P05-1022 E03-1005 P09-2035 P03-1055 W01-0521 W06-1606 P04-1082 P06-1110 J04-4004 P05-1067 P09-1064 P03-1013 H05-1100 N07-1051 P07-1019 P06-2089 D09-1161 W05-1506 W06-3603 P07-1080 W05-1512 E09-1037 P05-1044 W05-1504 P04-1061 D09-1085 P06-1072 D08-1091 P08-1109 D08-1022 P07-2052 P08-1023 N06-1020 P09-1063 N06-1021 H92-1026 P08-1006 W04-3201 P04-1013 W05-1513 P06-1055 P08-1067 P05-1010 P07-1079 W08-2102 P09-1059 P06-1033 W09-1104 P06-2041 D09-1087 N07-3002 W05-1505 P06-1043 E03-1008 W05-1516 P99-1065 C08-1081 D08-1016 J08-3003 P09-1041 W07-2217 P09-1007 C08-1095 P05-1012 W07-2218 D07-1111 C96-1058 P08-1061 D07-1070 C04-1010 Revised Design: P08-1068 P09-1039 E06-1010 I08-2097 D08-1059 D07-1014 D09-1060 D07-1101 P07-1122 N07-1049 P05-1013 W06-1616 D09-1058 N06-2033 D07-1099 D07-1015 Information Criterion-based E06-1011 W06-2922 W07-2216 D07-1119 I08-1012 D08-1017 W06-2920 J08-4003 D07-1096 W04-2407 P08-1108 D07-1097 D07-1013 N07-1050 W06-2933 N09-2066 H05-1066 P09-1040 W06-2932
  • 22. Connecting/Pruning Nodes Network Structure Learning      Proposed Method Proposed Proposed Method Propo Learning in Collaborative Settings Network Structure Learning yt+1 yt+1 yt+1 yt yt yt input index input index input index input index input index input index input index input index Model 0.4 a)a) Adding training point causes many b) Adding training point causes many b) Ad output estimates toto change. output estimates change. out output feature index output feature index output feature index 0.35 SL outpu Traditional Collaborative Proposed Method Proposed Approach Proposed Approach Proposed Method 0.3 0.25 Proposed Approach Proposed Approach yt+1 2 Use ychanges in in the estimates ⇥yt yt+1 ⇥2⇥to P (yt+1 ) Learning in Black-box Settings 0.2 Use changes the estimates ⇥yt Figure 5: T1 =⇤yt yt+1 ⇤ and the yt+1 yt+1 y t+1 generalization error G d ) generalization error G (x(xd ) t+1 0.4 0.4 value that it tries to approximate ⇥G 0.15 yt y y 0.35 (Section Section 3.1). Most importantly, yt t t 0.1 0.35 0.3 high values of ⇤yt yt+1 ⇤2 should cor- input index input index where yt+1 are the estimates after d , y, ) ) where yt+1 are the estimates after (x(xd d ydw input index input index 16% 0.3 84% respond to high values of ⇥G, since those are the points that are likely to be 0.25 0.25 P (yt+1 ) chosen. 0.05 P (yt+1 ) 0.2 0.2 Figure 5: T =⇤y y ⇤ and the 1 t t+1 0.15 Figure 5: that it tries to t+1 ⇤ and the ⇥G value T1 =⇤yt y approximate 0 0.15 value(Section tries to 3.1). Most importantly, that it Section approximate ⇥G y y high values of ⇤yt yt+1 ⇤2 should (Section Section 3.1). Most importantly, cor- 9 0.1 16% 84% high values of to high t+1 ⇤2 should cor-since respond ⇤yt y values of ⇥G, Proposed 0.1 yt+1 A−optimal 16% 84% respond toare thevalues of ⇥G, likely to be those high points that are since D−optimal thosechosen. 8points that are likely to be are the 0.05 E−optimal Transductive chosen. 0.05 Random Optimal Figure 3: Distribution of the ⇥ estimates 0 y y ⇥ 0 9 7 Proposed yt+1 in relation to the estimate yt and the y y y t+1 9 A−optimal D−optimal Proposed E−optimal Mean Squared Error y t+1 8 A−optimal Transductive f (x) f (x) true value y.xFigure 3: Distribution of y estimates D−optimal Random 6 E−optimal x 8 Optimal yx the Transductive x Random yx = yx = 7 ·x ⇥ x Figuret+1 in relation to·the estimate yt and the y 3: Distribution of the estimates 7 Optimal Mean Squared Error true value y. ˆ yt+1 in relation to the estimate yt and the 6 5 a)a) Adding training point causes many b) Adding training point causes few Mean Squared Error yt+1 true value y. (a) White (x) Model. f Box (b) Black Box Model. Adding training point causes many b) Adding training point causes few 6 x 5 yx ˆ yt ˆ y y* yx = ·x t+1 4 5 ˆ yt+1 output estimates to change. output estimates toto change. output estimates change. ˆ yt y* c Figure 4: For Black Box models only the inputs and outputs a b 4 output estimates to change. a b * c ˆ y y t 4 (b) Black Box Model. c 3 a b 3 are accessible, internal workings areFigure after4:after after training unlike for Figure 4: not accessible, point yFigure the training point y the training is added to the training set point 4: y the (making the 3 is added toadded to the training set (making the the is the training set (making 2 1 2 3 4 5 6 7 8 9 10 models only themodels [11].outputs of trainingofpoints points equal to t+1). White Box inputs and number Training Set Size 2 2 1 2 6 3 4 5 6 7 8 9 10 1 2 3 4 5 7 8 9 10 number number of training pointsequal to t+1). equal to t+1). Proposed Approach Training Set Size Training Set Size kings are not accessible, unlike for Figure 6: Evaluation of active learning Figure 6: Evaluation of active Error: lower criterions (Mean Square learning criterions (Mean Square Evaluation at active learning values are better, values are different of Proposed Approach yt+1 yt+1 Figure 6: Error: lower yt+1 2 estimate improvement in the the statistical significance level of 95%). values are better, values are different at criterions (Mean Square Error: lower Use changes in in the estimates ⇥yt yt+1 ⇥2⇥toto estimate improvement in the Use changes the estimates ⇥yt yt yt input index input index the statistical significance level of 95%). values are better, values are different at a) Adding a training point yt+1 yt b) Adding a training point the statistical significance level of 95%). generalization error G d ) generalization error G (x(xd ) influences many output es- input index influences only a few output
  • 23. t+1 f (x) 1 + x A x ⇤G p J 1 ⇤ 1 ⌅ A = X⇤ X + I A = X⇤ X + I xx A A X⇤ X = ⇥i i ⇤ , Conceptual Justifications (A + x x⇤ ) 1 = A f1 i (x) . ⌅p ⌅ p 1 + x⇤ AJ(⇥) = ⌅⌅t 1x y ⌅1 yt+1 ⌅ .⇤2 i=1 = ⇥ ⇤ + I. = ⇥i i ⇤ + I. i 2 ⇤ t+1 = (A + x⇤x⇤1 1 (X⇤ y + x 1y )⇤ 1 ⇥i ⇤ ⇥1 ⇥2 . . . pi ⇥im i ⇥m+1 =i=1 . = ⇥d = .. B T1 V ) ⇤ A xx 0 A X y i=1⌃ p m a ⇥ 1 1 ⌃x⌅ ⌅ . 2 ⇥2 ⇥ X⇤ X (A + x x ) ⇤ X ⇤G A X y ⇤ 1 y= i a⇥ 2 (A + x x ) 1 X⇤ y + (A + x x ) x1y . x A E G = = + B + V, + ⇤ 1x A ⇥ xi ⇥ i . JO 2 BJ V ⇤ 1 x⇥ A x⇥ = a ⇧ ⇥ x⇤ A 1 x⇥ = a i=m+1 JO i=m+1 JO ⇥ A 1 x x⇤argmax⇤J(⇥). A 1X y 1 p⇧p ⌅ ⇥2 ⇥ (A + x x⇤2) 1 X⇤ y = A 1 X⇤2y n i=m+1 x⇥ x⌅ i 1 2 x⇥ x⇥ 1 i=m+1 ⇥ i ⌅ ⇤X + I E G = +J(⇥) = ⌅⌅ B + V, y {⇥.i }i=1 1 + x A 1 x ⇤ A = XX⌅ X XX { { p 2}p }i=m+1 a2 x t ⌅ yt+1 ⌅ i a i i=m+1⌅ J = ⇥ ⇤ (A + x x⇤ ) 21 x y = A 1 x y ⌅ A 1 x x⇤ A %-1#x y '# ,# ⌅ p JO = 2 . X X⌅ X XO (a + 1) . i} 2{ { {⇥i }n ⇤ 1 1 ⇤3 1 / +$, ⇤#)$* 1 . . .,/')-'##,# JO JO = ⇥i i ⇤ + x⇥ (a + 1) i I. x A x x 1A + x'%' A x51 ⇥ B= E f (x) + x i=1 ) = A 1 (A g(x)x q(x)dx, . ( JO i=1 JO ⇤ ⇥ ⌅2 1 1A x y1(1- ⇤ + x⇤ A 3 1 x 2 D argmax J(⇥). A x x !#$%' a a JO a x⇤ ) 1 ⇤y B = + x E f (x) xg(x) = A x y (A q(x)dx, 1 ⌅2 ⇤ 1x 3 . 3 0$1 0 x⇤ A 1 x⇥ = a a JO a JT JT D V⇥ = E f (x) E f (x) q(x)dx. x A 1+ 14 16 ⇥ JO JT JT ⇤ ⇥ D ⌅2 ⇥ ⇤ ⇤ q(x)dx. ⇤ E f (x) =A1 1 x y A 1 x x⇤ A 11 x y ⇤ 1 1A ⇤ x x A ⇤ 1 ⇤ X y (1 + x⌅ A⌅ A ⇥1 x⇥ )2 1 1 ⌅ (1 +⌅ xa2 ⇥ x 1 )2 p f (x)t+1 + x tx ) X⇤ y = A 1 X⇤ y A x x A X !#$%'(!)*+, y ⇥2 1 p⇥ V =E (A JO = x⇤ i 2 2 ⌃⌃ ⇥ . a= 1 x⇤ ⇥ 2 ⇤ 1x ⇤ ⇥ ⇤ ⇤ 1 a= Figure 7: Decomposition of generalization error G into model error C, bias A variance V , where g denotes 1 + x A 1 +2 A ⇥ D ⇥ x 1 x 1 + x B, and 2x (a T J1) ⇥i + x⌅ A⌅ A t1 x . ⇥i.+ ⇥ ⇥ 1 i ⇥ ⌅ ⌅ J+ T i=1x x t 2 1 ⇥ yt ⌅ f⇥ ⇤ optimal function, ⇤is a⌅⌅1 1function⇤i⇤ are the1 ⇤ functions from a slightly di erent training set. 1 J(⇥) f= learned yt+1 ⌅’s = 1 X learned t t+1 , 1 ⇤ i=1 ⇥ ⇥ ⇤ =A 1 x y A x x A 1 + x AA x x xx A X y A x x AJO X y 1 xy A x 1 ⇤ ⌅ m xt ⇤X x ⌅ m ⇥2 xt ⇤X x 1 ⇤p ⇥2 ⇤ 1 ⇥2 1 ⌅ 1= ⌅ p t =A x6.2.1 Parameter Change-based 1 ⌅ 1 y = x⌅ A⌅x⇥xt1i ⇤ + a x⇥ i x ⇥⇥i +i . + 1 +AL 1 + x⇤ At1 ⌅x items thata 1likely toainfluence thex the most. 1 1 + x⇤ A 1 x ⇤ x(Settles et⇤al., 2008b) favors 1 A x t+1 + x⇤ A 1 model ⇥ x A xt ⇥i + i=1 ⇥ i=1 i=m+1 i=m+ 1 ⇤ changes A model’s parameters⇤ yfor the better, i.e. approach the optimal parameters, it x x 1A x Parameter Change-based are ⇤ ⇤ 1 1 + ) x xis then beneficial to select the + that A x are . 1 X⇤ y (A + x x x A y11x Assuming x A⇤ 1 xin an itemA ⇤has the1greatest impact on the model’s parameters: A = A x x ⇤ t )21 x x x A (y thaty 1 ⇤p =A 1 x y p ⇥ ⇤ ⌃⌃ p ⇥ ⇥⌅ ⇥ ⇥ 1 1 y ⌅ = = x⇤ ⌅ J(⇥) = ⌅⌅t yt+1 ⌅1 + 1 X A ⇤1 x ⌅x 2 1 t+1 . , G = (x )⇥ X A I,x , ⇤ = A 1 X⇤ y. ⌅ A⌅⌅t1=t = ⇥ x⌅ x⌅ xt x⌅ A 1 + = ⇤ + y Y1 T Tt⇥(x ,y)), ⇥ change X x x⇥ x A x 1 px (22) ⇥ 1i i i=m+1 a + x tA a E L( a a= ⇥ x⇤i=1 i=1 ⇥ i 2 ⇥ i t ⇥i +i ⇥i + ⇤ I where T ⇤ t+1 ⌃m⇥ + ⇥ A 1 q(x) x⇤ ⌅ t )⌅ parameterare the model’s parameters estimatedyfromanthe current training ⇥TtrainingTset T,y)and Li=1model’s m ⌃⌅i ⌅⇥ x⌅ ⌅⇥ p⇥ 1 1 + 1 1 p ⌃x⌅ ⌅⇥ x⌅ ⌅⇥ . p(x) ⇤=x (y estimates after a hypothetical rating of set , and ⇥(x item xa 0 added to the 1 is , are the a m the loss is = ⌃p ⇥ = ⇤ 1x t . t+1 1 function that measures x y erences between the parameters. ⇤ y A xx A ⇤ 1 the di 1 A xx A X ⇤ 1 ⌅= ⌅ = ⇥2x⇥ x⇥ i t xti ⌅ + ⇤ + 1i 1 ⇥i ⇥ + ⇥ 2 i ⇥ xi ⇥ i t xt i i (x) ⇤= q(x) 1 + x =A 1 x y A ⇤ ⇤ A ⇤ 1 ⇤⇤ t x⇥ i=1 i=1 + i x⇥ i i=m+1. i=m+1 x⇤ A= x A x 1(y ⇤ x 1 t ) . i t+1 t 1 ⇥i + ⇥ ⇤ 1 +Variance-based decomposed into + x A xmodel error C (the di erence between the opti- yt+1 approachtthe error is ⇥ 6.2.2 ⇤ y X ⇤ t+1three (A 1 xx x ) (X y + x y ) ⇤ components: ⇤1 1⇤ ⇤ i=1 i=m+1 1 ⇧p⇧ 1 i=m+1 x⇥ x p ⌅ = X X +x⇤function approximation Agiven1 + xAA x +the A function f ), bias B (the di erence between ⇧ n ⇤ A 1 ⌅ 1 + malI, 1 x In this A = 1 x ⌃ x⇤ g, 1 x current model, and ⇤ true X y the 1 ⇤p ⇤ ⇥2 i=m+1 ⌥ =A i )x y 1 ⇥2⇤ the current approximation ⇥ ⇤ an i=m+1 x⇥ i ⇧ n min q(x ⇤ A 1 xIn(y A 1 x fhave:) optimal one g), and+ x AV⇤(how1much y + (A approximation f 1 x y . xwe andt = (A variance 1 x X⇤ the function + x x⇤ ) ⇤ x ) ⇥ I ⇤ ⌅ ⇥ ⌃ ) + x words, f (xivaries ).yi ,⇥ 1 0 other 1+x a ⇤ ⌥ q(xiyt+1 p(xi ) = X 2 ) ⇤ yt ⇥ . G = C + B + V. (23) p 1 ⌃⌃ ⌅ ⇥ ⇥⌅ ⇥ ⇥ p min A i=1 f (xi1)x (yi A y x t One1⇤ ) x⇤ A 1 x + ⌅t , ⇤ solution (Cohn et al., 1996) is to minimize the variance component V of the error by assuming that the x⌅ A⌅ A t1⇥t ⇥ 1 ⇥ x ⇥ 1 x x x ⇥ x ⌅ xt x ⌅ , , ⇥ i i t i i p(xi ) = . bias component becomes negligible (if this assumption is not satisfied then this method may not be e ective). i=m+1 J( ) = variance ⇤a number of⇥2 i=1 i=m+1 ⇥ ⇤ ⇥ 1 1 + x⇤ A Theret+1 the model’smethods proposed that aimJOselect training inputs seeks to selectcertain measure points 1 x are y ⇤ ⇥⇤ of yt parameters. The A-optimal design (Chan, 1981) for reducing a training input of the to JT JT JT ⇤ 1 as ⇥2 1J( ) = (y x⌅ ⇧ )2 x⌅ A 1 X⇥⌅ X⇥ A sox to minimize the average variance of the parameter estimates, the D-optimal design (John x⇤ A 1 A 1 x Draper, y 0 x⇤ ⇤ 1975) seeks to maximize the di erential Shannon information content of the parameter estimates, and the t ⌅ 2 ⇤= al., 2006)+ x tox⇤ ⇥ 1 = 1 1 (1 + x A 1 x )Transductive Experimentaltdesign (Yu et ⇤ (A 1seeks⇥⇤ )representative training points that may allow . find A ⇤ ⌃⌃ ⇥2 J( ) S= ⇥⇤t+1 yt ⇥2 0= retainingcomponent,1also 1= 1 ofaccount Aexistense of(x⇤model1inx(Sugiyama, 2006),+ x A to the JT JT 1 J y ⇤ = variance mostA the x (y into xxtesttpoints. X ALthe AAerror2component.1 in addition x ⇤ of information ⇥ ⇤ ⇤ takes the ⇤ ) ⇤ The Xmethod ) x. x⌅ A⌅ A t1 xt ⇥2 ⇥ x 1 x = JR , yt+1 y⇥= X x A x ⇤ ⇤t 1 + the .O = J ⇥ ⇥ , xt ⇤X x ⇥ J( | y = r) JP 2 = 1 1 + x⇤ A 1 x ⇤ Image Restoration-based (1 + x⇤ A 1 x⇥ )2 xt ⇤X x ⇤⇤ ⇤ ⇤ d d ⌅2 ⌅ y x t 6.2.3 ⇤ ⇥ ⇤ ⇥2 1 ⇥⇤problem of predicting the user’s preferences as one of image restoration1(Nakamura ⇥ 1 ⌃⌃ 1 ⌃⌃ ⇥ ⇥⌅ ⇥ ⇥ 2 = ⇤) , 1 ⌅⇧ 2 x A X XA x. It is also possible to ⇤ treat the (x⇥ A x⇥ ) 1 2 xt ⇥X x ⇤ 1 x⇥ A ⇤ xt ⇤ A xx A 1 ⇤ X y ⇥ ⇥ 1 x⌅ x⌅ xt x⌅ . . JR = (y1 + x t A x x JO = , J⇤ of 1 ⇤ Abe, 1998), that is, based on our limited knowledge = a user’s preferences (a1 (A + x x ) X y = A X y . partial picture), we try to restore ⇤ user’s likes and dislikes.TThe AL task is+ x⇤ A 1 x )training points that would ⇥ i ⇥ i i t i the complete (1 + x the picture of A ⇥ 1 x )2 ⇥ (1 then ⇥ select the 2 to ⇥ 1 + x A 1x ⇤ xt ⇤X x xt ⇤X x i=m+1 i=m+1 J( ) P (y = r)J( JS = x⌅ A 1 X⇥⌅ X⇥ A 1 x , best allow us ⇤ ⇥2 to restore the “image” of the user’s preferences. It is interesting to note that this approach satisfies ⇤ 1 r 2 the desired properties of the ALx A outlined in Section 2. For example, if a point already exists in aJ methods xt region, J( ) = ⇥⇤ y ⇤ y⇥ xt ⇥X x ⇥ JO JT JT T x⇥ x⇥ X⌅X⌅ X JP = (1 + x⌅ A 1 x )2 .t+1 tT thenJ = sampling neighboring points the image in that region could likely be restored. This approach also without . ⇤ ⇥ ⇥ ⇤ edges of 2 may favor sampling close to the (1 + x A X X 1 x ) image components (decision boundaries). X x⇥ ⇥
  • 24. (Section III-A1). Size of the node reflects degree of the node (scaled logarithmically). Connecting People relation to number of alumni nodes differs. Stanford University has a significantly higher ratio of companies per alumni in leadership roles, followed by Harvard, trailed by Berkeley, and subdued edges in Figure 2. The distance from the universities University Alumni to the cloud of ‘financial’ clusters also varies. In particular, Stanford MIT Stanford and Berkeley are rather close to the financialPerson Other Nodes Financial Org. Company cloud. t t fi Collaboration Networks Harvard MIT. A high ratio of company nodes indicates that alumni This may be explained by the geographical proximity of these Berkeley University b have been involved with multiple companies - either through universities to one of the largest sources of venture funding – Size (Centrality log-scaled) l employment, advisory or investment activities. In addition, Silicon Valley. While universities themselves are not embedded o the number of highly connected alumni (large nodes with within the financial clusters, a noticeable proportion of alumni f many connections located on the perimeter) differs significantly are deeply connected within the financial clusters by having N University Alumnus between universities (we further explore this in Section III-B). Company direct or indirect relations with multiple financial organizations. a One particular characteristic of highlySize (degree log-scaled) connected alumni stands Stanford has the largest number of alumni connected to the a out, namely their collaboration patterns. Stanford’s densely financial cluster, followed by Harvard (even though university T connected alumni are highly likely to collaborate with fellow itself is relatively distant from the financial cluster); followed a alumni (indicated by the company nodes being pulled away by Berkeley, and only a few alumni from MIT. The proximity t from highly connected alumnus towards other less-connected between alumni and their alma matters appear to differ signif- l alumni in the center). In the networks of other universities, the icantly. Berkeley alumni tend to be clustered together, MIT to t collaboration of highly connected individuals with their fellow somewhat lesser degree, and Stanford and Harvard alumni are N alumni is evidenced but to a lesser degree. rather dispersed. Proximity between universities differs as well. Harvard alumni appear active in leadership positions in Stanford and Berkeley are close together (many alumni hold n technology-based startups, even more so than MIT alumni leadership positions in the same companies). One of the likely v (Figure 1b vs. 1c). A possible explanation for the relatively explanations for this network proximity is the geographical t lower level of MIT alumni may be attributable to the focus of proximity of both universities to Silicon Valley where many of b (a) Stanford University. (b) Harvard University. (c) MIT. (d) UC Berkeley. this dataset on leadership positions in the organizations. While the investment firms and startup companies are located. Harvard S Figure 2: Inter-University NetworkasNetwork and MIT do not appear to have (between relations with other Inter-University strong Stanford, Harvard, p Figure 1: Intra-University Networks. Networks of the above universities are expanded in a breadth first manner so in the depth engineers play a key role, they often do up to a technology universities in these settings. MIT, Berkeley) (Section III-A2). Network is obtained by start- U of 2, (showing university, alumni and companies they are associateddevelopment capacity rather than in the leadership activities) that with through employment, investment or other positions ing with the nodes of the above mentioned universities and t (Section III-A1). Size of the node reflects degree of the node (scaledare visible in public relations communications. Some support logarithmically). for this explanation may be seen in the Figure 2 relatively large performing a breadth-first expansion up to the depth of 3. p distance between Microsoft and University of Washington, even e though a large number of engineers atUniversity Alumni Other Nodesindeed Microsoft are w relation to number of alumni nodes differs. Stanford University has a significantly higher ratio of companies per alumni in from University of Washington. Stanford Financial Org. level entities/nodes that are linked to previous levels including MIT 2) Inter-University Network: A graphic representation of Company financial organizations, company employees, etc. Since we B leadership roles, followed by Harvard, trailed by Berkeley, and Harvard Person MIT. A high ratio of company nodes indicates that alumni the alumni-based inter-relations between Berkeley universities, shown University are primarily interested in relationships among alumni, all of have been involved with multiple companies - either through in Figure 2, was produced as follows. Four universities were Size (Centrality log-scaled) other entities are faded out, except for the above mentioned n employment, advisory or investment activities. In addition, selected for analysis: Stanford University, University of Califor- universities and their alumni. In addition, we glimpse at the o nia (Berkeley), Harvard University and Massachusetts Institute relations between alumni and investment firms (a very impor- n Betweenness Centrality Betweenness Centrality the number of highly connected alumni (large nodes with Betweenness Centrality Betweenness Centrality many connections located on the perimeter) differs significantly of Technology (MIT). From these nodes we have performed tant factor for entrepreneurism). Therefore, nodes of financial l between universities (we further explore this in Section III-B). breadth-first expansion up to the depth of three: 1st level organizations are not faded out. q One particular characteristic of highly connected alumni stands being alumni of these corresponding universities, 2nd level Two distinct groups – universities (in the lower left corner) n out, namely their collaboration patterns. Stanford’s densely are companies with which alumni have relations, and 3rd and financials (in the upper right corner) – are visible in the S connected alumni are highly likely to collaborate with fellow 1 alumni (indicated by the company nodes being pulled away D from highly connected alumnus towards other less-connected p alumni in the center). In the networks of other universities, the i collaboration of highly connected individuals with their fellow alumni is evidenced but to a lesser degree. e Harvard alumni appear active in Alumni Indexleadership positions in Alumni Index Alumni IndexIndex Alumni University F (a) (a) Betweenness Centrality Alumni Nodes in so Networks (University and (b) Betweenness Centrality Alumni Nodes in Networks (University andand Betweenness Centrality of of even more Networks (University and (b) Betweenness Centrality of of Alumni Nodes in Networks (University technology-based disconnected). startups, Alumni Nodes in than MIT alumni Other Entities (Company, People, Financial Org.) m alumni nodes are are alumni nodes disconnected). alumni nodes are are connected). alumni nodes connected). (Figure 1b vs. 1c). A possible explanation for the relatively Size (Centrality degree log-scaled) t Figurelevel of MIT alumni may be attributablealumni nodes thethe network (connected thethe university node (b)), and (disconnected Figure Betweenness Centrality (y-axis) of alumnithe focus of network (connected to to university node (b)), and (disconnected lower 4: 4: Betweenness Centrality (y-axis) of to nodes in in t University-Company Network Figure 3: Universities within the Business Network (partial c this dataset on leadership positions The x-axis corresponds to alumni ordered in descending order of centrality for each of the from thethe university node (a)). inx-axis corresponds While from university node (a)). The the organizations. to alumni ordered in descending order of centrality for each of the
  • 25. — —- Generalized Assignment Problem —- Connecting People Contents —- Generalized Assignment maximize Generalized Assignment Problem p, choose a Problem — Objective: given a paper M given a Assignment Problem collectively possesses Generalized a fixed size s) that Objective: ⇥ M (ofpaper p,given a paper subject to a gro —- the most expertise about p: a groupa ofp, choose Objective: choose Objective: given a paper p, choose group of experts group of experts experts R(M Expertise Finding Group Formation M ⇥ M (ofgiven ⇤papers) that fixed sizeof experts M ⇤ M a fixed size (ofchoose a group possesses collecti M a M p, a collectively s) that Objective:⇥ M (of a fixed size s) that collectively possesses M size s) most collectively possesses the most expertise about p: the that expertise about p: the most expertiseexpertise about P the most about p:R(M, p) = p: maximize m2M r (m, p) Task Description Task Description 6'1'.% |M = R(M, p) ⌅= P subject to maximize R(M, p) = m2M r |(m,sp) P maximize R(M, p) = m2M r (m, p) P P !#$%'()*+*,-).(./) maximize R(M, p) |M | = s r R(M, p) = subject to maximize (m, p) = m2M 7%2*.*.1% Limitation X |M | = s subject to Group 896').*.1% subject to subject = s r (m, p) . |M | to Expertise⌅=is not additive: |M | R(M, p) X m2M — Limitation – R(M, p) ⌅= X p)r.(m, p) . R(M, p) ⌅= r (m, Training Set:— = (XT additive: iExpertiseT Estimation m2M 4'#')(5')% Expertise is not , YT ) = {(x , f (xi ))xi 2X } Limitation T Group m2M Training (and = (XT , Y Y ): RT Function learned from XSet: Tcorresponding ) = {(xi , f (xi )) Limitation – — b !#$%'#()*+,-.% Expertise is not additive: TAssumptions T T bT ) = L(RT , f ) b Expertise is not additive: Generalization error: G(R ⇤ Group FunctionEstimation from XT (and correspon Expertise learned /'010%('2*(%++')3% – – Assumptions M—- athors of paper p; so p are Group Expertise Estimation Generalized Assignment Prob Generalization error:T0, where =L(⌥ andf ) b b ⇤ R(M, p) R G(R ) =M1,RT , p = Researcher Profile Researcher Profile Researcher Profile Mp are Expertise EstimationG(= ) ⇤ T Group — — min Assumptions athors of paper Xp; ⇤ so R(Mp , p) ⇤ b M (-.7)*:;7'%$.-='1'% R(M, p)of—- where M ⌥ R(M ⇤ ,Ø. given a paper p, c —- Assumptions — Objective: = 1, and T Knows — p are athors M ⇤ = 0, paper p; so Mp = p) Knows Knows g: optimalare athors Assignmentp; so R(Mpa p) ⇤min G( b t Generalized(in the ⇤ ⇤ function sollution space) ⇤ , Problem of paper ⇥ p R(M, p) = 0, where M ⌥ MpM Ø. ⇤M (ofM ⌥Problem RT ) —- Mp—- GeneralizedR(M,=choose a fixed Tsize s) = Mp 1, R(M, = and b learned function given aM ⌥ Assignment group. of experts R: R(M, p) = 0, where paperProblem ⇤ Objective: Assignment pp, p) = Generalized M Ø. X Generalized Assignment Problem most ⌥ Mp Mp about p: the M expertise⇤ ⇤ b M ⇥ M (of fixed size p, choose a⌥groupchoose a Objective: given a slightly a paper Mp possesses Objective: given di⇣erent training Ri ’s: learned functionsaR(M,paper s) that collectively of experts p, Objective: given a paperfrom a p) = a group theexperts set.spac M p, function p) = of . sollution choose optimal (of p: (in the g: M use Learn R group expertise. B (ofV most expertise that collectivelycollectivelyestimate + ⇥ and ⌘⇥ M abouta s)and⇤ size ⇤ to . possesses EG = Learn abfixed (of aitfixed sizeb fixed use its) that colle M R C to R(M, Mp + M size s) estimate that possesses M ⇥ M ⇣ Mp b expertise the = R R(x)useg(x) mostfunction aboutP B most expertise learned expertise 2 Learn b and R: the estimate group expertise. maximize E bthe mostabout p: about p: — — p: R b it to it to YT R ’s:2 T = (XT , functions (x= P T ⇣ Training iSet: use maximize) =R(M, fp)expertise.}r (m, p) b ⌘ Learn R and learnedestimate{(xi , fromxia slightly di⌘ group i )) 2X maximize Set: p) = (X Y, Yto) = { Training P T subject T b — b b m2M V = R ER(x) Function = = B from X p) =R(M,i 2XT= | = T r (m, p) — Training Set: EG (XT , YsubjectTto, f (xicorresponding s T ): RT T learned +)V {(xC =+ maximize T R(M, i(and ))x r|M m2M (m, p) } (x)) ⇣ maximize R(M, p) = ⌘ m2M Generalization X subject TT))= {(xR f (x )) R s X (and Training Set: = Function learned from C = (g(x) fsubjectTto T (XT , Ycorresponding iYTxi|2X T} G( b |M |2i , Function learned from error: Challenge= T , f )|M): = T T b (andRto = L( b s 2 b b Function = ER(x) b b y corresponding G(): R) = Challenge Use changes B the estimates Xyg(x)t+1 to to from T (and in learned RT ) = L(RTsubject error: YTimprovem b Generalization estimate RT T |M Generalization error: G( additive: , t bf ) 2 b Challenge Generalization not Expertise ⇣ Challengeis ) generalization error G(x error: Expertise RT not additive: G(RT )⌘2 L( is ,bT)) b = min b RG( f b Expertise estimates b G( V = b where y is are the isR additive: R ,T) was not Expertiset+1 not additive: ER(x) (xbTy )X added to the train X after min !#!$% R(M, p) ⇤=G(RT ) r (m, p) X m g: optimal function (in XT number ofbtraining points is eq . the 2 min space) Gt : generalization error when the sollutionX C =function p) f (x)),space) added. tor p) R(M, ps X m2M b (g(x) sollution yp)Tr (m, m2M the ⌅= . R(M, X ⇤= R(M, (m, training g: t+1 : R: –learned (in the after (x m2M is generalization error ⇤= G optimal function R(M, ) p) p) !#$%'#()*+,-.% m2 ⌅G = Ritoptimal :functiong:– in insollution space) (in the t+1 R: (in the a b learned–functionchanges optimal functionerrortraining set b Group Expertise Estimation estimates y g: ’s: learnedimprovement the slightly different G Use Gt+1 functions from generalization bt y sollu b – !#!$% — EGGroup Limitation b learned V + =B function Estimation Ri ’s: Expertise+ExpertiseR: slightlyExpertise Estimation R:Assumptions C b b generalization⌘error G(x ) b Grouplearned learned functions learned function ⇣ functions from a different training set. ’s: b ExpertiseGroupa slightly different training se RiM ⇤ are Estimation 2 is not additive:, p) = 1, and from B= ECAssumptionsg(x)bpaper p; so R(Mp EG = B + Vp +R(x)⌘ y athors of ⇤ ⇣ EG = B + V 2 C min G the ⇤estimates after (x y aret+1 M max ⌅G. Assumptions ⇤ where+bt+1 i ’s: learned functions from ,a s RAssumptions ⇤ , p) = 1, and M⇣ are athors⌘2 x paper =p = R(Mp b R(M,g(x) 0, where MR(M ⇤ , xp)Ø. p) = of ⌃ p; so B ⇤ are R(x)p bof – generalization perror = 1, and⇤ numbe Mp= EathorsGb : paper p;⌘2 ⇤ so V = RR(x)b 0, where Mare + = Ø.when M E ⌘ R(x) EG p⇣ B ⇤ V + M ⌃ the B R(M, tp) = g(x) ⇤ M= ⌃ MpathorsC of ⌘ p E paper p; R(M,⇣p) = 0, where M ⌃⌘ Expertise Estimation 2 . b = (g(x)Group 22 p R(M, b = 0, where (x , yM ⇤ 2 M = Ø. R(M, p) = ⇣Gt+1 : generalization error M ⌃⇤M ⇤ ⌃ ) is C b V = R ER(x) f (x)) B = ER(x) ⇤ g(x) p p) after M Mp V = R Assumptions R(M, p) p b ER(x) b M ⌃ M= p C = (g(x) changes in the Use f (x)) ⇤ Gt estimates improvement in. genera ⌅G2 = ⌅G2=JGt+1 : ↵bt ⇤ yt+1 ↵2 Mp estimate imp R(M, + Kp)⇣ = y b . ⌘ to⇤ C Learn R and use it to estimate2paperexpertise. R(Mp = (g(x)Mp (x)) athorsb ofMgroup 2 so R(M b f are ⇤ — b semantic and structural to p; Use generalization error G(x )= t Rt+1 ER(x) 2 ⇤ improveme p changes in the estimates yy yyt+1 ↵ b estimate = ↵b 2 J V bt b b Use b R(M, estimates y both features. and yt+1 in Kp) =group ↵bt ⇤M y ↵ to = Ø. generalization error G(x ) the =2 y0, where(x t+1t+1was added to th bwhereuse R are the estimates after group⌥) Mpestimate imp Learn and use it to estimate y , y expertise. Learn RUse changesto estimate b it expertise. b generalization errorstructural(g(x) t , y f (x))2 ⌦ training point y b Use ensemble predictive structural features. model. Use both semantic ) when the number of G(x and features. b b semantic estimates = (x , y ) was added to the train t+1 Use both t : generalization error G where yt+1 are theand C after where yt+1 are predictive model. , y , yis) was added max — b Use ensemble Learn b in ) xR(M, = is tra Use ensemble predictivethe Use changes (x training t+1estimat estimates after min G to M th Gt : generalization error model.the after (x of useadded to the x ↵ —- Gt+1 : generalization error Y )R and, fthe it to p) = equ when number points estimates GtTraining Set: T = (XTwhen =in numberi ))xi 2XTerror :— Gt Gt+1 : improvement {(xi ⇤(x of training point ⇤G generalization true output the semanticnot training se = sinceerror error (xboth is generalizationaccessible. , T } Training Set: T fromTX T (and{(xy, f (x ))xand }struct Use , y valuesiy) isto 2X —t+1 :: generalization the after ) #$'()(*+,'%),!#!$% G⌅G estimate generalization(x addedare the Y G Function learned= error, Yf (x= error } added to ): RT (X ) G(x i ) Training Set:Ggeneralization= {(xi afteri ))xcorresponding T T the tra : ⇤G = Gtt+1 T =: (XT ,⇤YT ) Use ,Tgeneralization ierror , improvement inensemble Tpredictive mode b t+1 i 2X b
  • 26. Connecting Models Operationalization of complex conceptual models Motivation Internalization hFp://cmap.ccdmd.qc.ca/rid=1225215801935_1377957481_826/  
  • 27. Model Diversity Table 10.1. Motivation Terms: Author by Factor Matrix Author Wlodkowski Paulsena Donald Keller MacKinnon Panitz Feldmanb Nuhfer Farmer Theallc Pintrich Forsythd Chickeringe Factor Inclusion X X X X X Community X X X X Climate X X Ownership X X X X X X Attitude X X X X Affect X Interest X X Awareness X X Attention X Enthusiasm X Meaning X X Relevance X X X X X Value X X X X Competence X X X Empowerment X X X Confidence X X Expectancy X X X Leadership X X High expectations X X X Structure X X X X X Feedback X X X Support X X X Satisfaction X X Rewards X X a Paulsen and Feldman (Chapter Two). (Theall    Franklin,  1999)   b Feldman and Paulsen (Chapter Seven). c Theall, Birdsall, and Franklin, 1997. d Forsyth and McMillan, 1991.
  • 28. Complex Modeling Typical Approach Feature Extractors Features Sub-Models Sub-Models Aggregation Selection Conceptual Conceptual motivation relatedness Expct Val T Expct Val T Text (tweets) label A1 .……………… sentiment Cogn Diss T Cogn Diss T ... ... .……………… A2 .……………… Textual Classifier Computational .……………… part of spch M1 M1 A3 .……………… dependency M2 A4 M2 ... ... Dataset Construction Feature Extraction Sub-Modeling Ensemble Construction
  • 29. Summary --------- --------- --------- --------- --------- AI --------- --------- --------- --------- --------- --------- --------- --------- --------- --------- Networks  are  crucial  for  learning   •  use  AI  methods  to  construct  /  opTmize  networks   –  connecTng  contents   –  connecTng  people   Concept Extraction concept concept concept concept concept concept concepts concept concept Group Formation documents –  connecTng  people    contents   tasks –  connecTng  models   context (documents) Semantic Mapping concept concept concept concept Influence Estimation concept concept concept concept concept concept concept concept concept concept interaction log concepts concept concept Knowledge Level concept concept Estimation concept concept concept concept concept concept concept concept concept concept concepts