Design and Support Recommendations
from Data Visualization Research
July 17, 2014
Science Boot Camp Southeast
Raleigh, NC
#BootCampSE14
Angela Zoss, @duke_vis
Data Visualization Coordinator
Duke University Libraries
Using research to inform design
Expert suggestions/heuristics
http://bit.ly/tufte_vdqi http://bit.ly/bertin_sg http://bit.ly/few_smn
Using research to inform design
Empirical verification and elaboration
http://bit.ly/cleveland_egd http://bit.ly/ware_iv http://bit.ly/wilk_gg
Demo data for today
http://bit.ly/bcse_zoss
POSITION IS EVERYTHING.
@moritz_stefaner
The research shows…
•  Rotated text is harder to read
Byrne, M. D. (2002). Reading vertical text:
Rotated vs. marquee. In Proceedings of the Human
Factors and Ergonomics Society 46th Annual Meeting;
Santa Monica,CA. Human Factors and
Ergonomics Society: 1633–1635.
http://dx.doi.org/10.1177/154193120204601722
The research shows…
•  Rotated text is harder to read
Byrne, M. D. (2002). Reading vertical text:
Rotated vs. marquee. In Proceedings of the Human
Factors and Ergonomics Society 46th Annual Meeting;
Santa Monica,CA. Human Factors and
Ergonomics Society: 1633–1635.
http://dx.doi.org/10.1177/154193120204601722
Text orientation
State population from 2010 census
http://en.wikipedia.org/wiki/US_states_by_population
Easy in Excel
Text orientation
State population from 2010 census
http://en.wikipedia.org/wiki/US_states_by_population
Easy in Excel
Text orientation
Easy in Excel
The research shows…
•  Rotated text is harder to read
•  People are very good at reading bar length,
x/y position
Vernier acuity:The ability to see if two line segments are
collinear.Accurate to about 10 seconds of arc or 1/10 of a pixel.
Ware, C. (2013). Information visualization:perception for design,
third edition.Waltham, MA: Morgan Kaufmann Publishers.
http://www.sciencedirect.com/science/book/9780123814647
Perception of length/area
Easy in Excel
Perception of length/area
Easy in Excel
Perception of length/area
Easy in Excel
Perception of length/area
Advanced in Excel
http://peltiertech.com/Excel/Charts/DotPlot.html
The research shows…
•  Rotated text is harder to read
•  People are very good at reading bar length,
x/y position
•  But even our positional acuity is no match for
high data density
Data density
State population vs. Number of seats in U.S. House
http://en.wikipedia.org/wiki/US_states_by_population
Easy in Excel
Data density
State population vs. Number of seats in U.S. House
http://en.wikipedia.org/wiki/US_states_by_population
?
Easy in Excel
Data density
Fill transparency at 100%
Easy in Excel
Data density
Fill transparency at 50%
Easy in Excel
Data density
Both axes converted to logarithmic scale
Easy in Excel
Data density
Ranges edited, vertical axis switched to base 2
Easy in Excel
Data density
Population mapped to horizontal axis,
seats in house mapped to size,
random “jitter” added as vertical axis values
Intermediate in Excel
The research shows…
•  Rotated text is harder to read
•  People are very good at
reading bar length,
x/y position
•  But even our positional acuity
is no match for high data
density
•  People are not as good at
differentiating angles, areas
Cleveland,W. S., & McGill, R. (1985).
Graphical perception and graphical
methods for analyzing scientific data.
Science,299(4716), 828-833.
http://dx.doi.org/10.1126/science.229.4716.828
Angles, wedges, circles
People are bad at comparing areas of shapes or judging certain relationships.
If precision is important or data values are very similar, use bars or scatter plots.
http://de.slideshare.net/vis4/making-
data-visualizations-a-survival-guide/25
http://de.slideshare.net/vis4/making-
data-visualizations-a-survival-guide/162
http://www.leancrew.com/all-this/2011/11/
i-hate-stacked-area-charts/
Visual math
http://eagereyes.org/criticism/visual-math-wrong
If the chart makes it hard to understand an important relationship between
variables, do the extra calculation and visualize that as well.
http://bit.ly/SFeAwzhttp://bit.ly/PszKw0
Avoid special effects
http://bit.ly/3dpiebad
COLOR IS DIFFICULT.
@moritz_stefaner
The research shows…
•  People have trouble
differentiating between
more than 5-7 hues
?
?
http://colorbrewer2.org/
Healey, C. G. (1996). Choosing effective colours for
data visualization. In R.Yagel and G. M. Nielson (Eds.),
Proceedings of the 7th conference onVisualization '96
(VIS '96), 263-270.
http://dx.doi.org/10.1109/VISUAL.1996.568118
Qualitative color classes
With categorical/qualitative variables (e.g, states, genders,
political parties), use at most 5-7 hues.
States by population and house seats, colored by region
Requires 4 separate data series
Intermediate in Excel
The research shows…
•  People have trouble
differentiating between
more than 5-7 hues
•  People have trouble
differentiating between
more than 5-7 shades
http://colorbrewer2.org/
Gilmartin, P. and E. Shelton. (1990). Choropleth maps on
high resolution CRTs:The effects of number of classes and
hue on communication. Cartographica,26(2), 40-52.
http://dx.doi.org/10.3138/W836-5K13-1432-4480
Ordered color classes
With classed/graduated variables (e.g., rating scores, age groups,
any number that has been split into groups), use at most 5-7 shades.
States by population and house seats, colored in 4 x-axis value groups
Requires 4 separate data series
Intermediate in Excel
Continuous color
With continuous variables (e.g., population, rainfall, timestamp),
the only option in Excel is conditional formatting of cells.
https://www.census.gov/hhes/migration/data/acs/state-to-state.html
Migrations between states, colored continuously
Easy in Excel
Continuous color
Depending on your data, a continues gradient might group too many
elements into a small range of lightness. You can also transform the
data (e.g., log) or create discrete classes for more control.
Migrations between states, colored in 4 classes
Requires conditional formatting “classic” rules for value ranges
Intermediate in Excel
The research shows…
•  People have trouble differentiating between more
than 5-7 hues
•  People have trouble differentiating between more
than 5-7 shades
•  Rainbow color gradients are very problematic
“Rainbow Color Map (Still)
Considered Harmful”
Borland, D., &Taylor, R.M. (2007). Rainbow
color map (still) considered harmful. IEEE
Computer Graphics and Applications,27(2), 14-17.
http://dx.doi.org/10.1109/MCG.2007.323435
Perceptual ordering.
(a) We can easily place the gray paint chips in order
based on perception,
(b) but cannot do this with the colored chips.
Borland & Taylor (2007)
Confusing
Spatial contrast sensitivity function.
We can see detail at much lower contrast in the
(a) luminance-varying gray-scale image than with the
(b) rainbow color map.
Borland & Taylor (2007)
Obscuring
Four data sets visualized with
(a) rainbow,
(b) gray-scale,
(c) black-body radiation
Apparent sharp gradients in the
data in (a) are revealed as rainbow
color map artifacts...
The sharp gradient found at the
center of the second data set... is
not found in the corresponding
image with the rainbow color map.
Borland & Taylor (2007)
Actively misleading
Related: Salience
Rainbows also cause salience problems; some colors in the inner
part of the rainbow “pop out” more than colors at the extremes.
http://dx.doi.org/10.1038/nmeth.1762 http://mycarta.wordpress.com/
2012/12/21/comparing-color-palettes/
Instead of rainbows…
Solution: Use a single hue, varying luminance
If you want color to show a numerical value, use
a range that goes from white to a highly saturated
color in one of the universal color categories.
http://shar.es/CfbSd
http://www.flickr.com/photos/sadrzy/4154089647/
ColorBrewer
Cynthia Brewer, PhD – Penn State
http://colorbrewer2.org/
The research shows…
•  People have trouble differentiating between more
than 5-7 hues
•  People have trouble differentiating between more
than 5-7 shades
•  Rainbow color gradients are very problematic
•  For highest contrast, limit colors and vary luminance
Color versus position
Do you really need color at all?
Intermediate in Excel
Color versus position
Do you really need color at all?
Intermediate in Excel
Color versus position
Do you really need color at all?
Easy* in Excel
*Creating charts with manually-selected y values is easy and very useful.
Adding labels, though, can be harder. Sometimes it’s easiest to add them manually.
Visual contrast
If you use color sparingly,
you can save it for contrast.
Intermediate
in Excel
Visual contrast
Contrast is important to direct attention and improve clarity.
It can also shield against projection/printing issues or color
interference effects.
http://shar.es/CWktB
Times to use color
Times to use color
•  When position is insufficient (lines crossing)
as opposed to:
http://vis4.net/blog/posts/doing-the-line-charts-right/
Times to use color
•  When position is insufficient (lines crossing)
•  When it will aid pre-attentive processing
Count the 4s.
173658103837575063348181736401016254
539319123938525616173943987139874619
319586716628309897273164613984019358
094285976205897629835921873589321759
871059283198254781237598698127359812!
Times to use color
•  When position is insufficient (lines crossing)
•  When it will aid pre-attentive processing
173658103837575063348181736401016254
539319123938525616173943987139874619
319586716628309897273164613984019358
094285976205897629835921873589321759
871059283198254781237598698127359812!
Count the 4s.
Times to use color
•  When position is insufficient (lines crossing)
•  When it will aid pre-attentive processing
•  When it reinforces semantic content
Lin, S., Fortuna, J., et al. (2013). Selecting semantically-resonant
colors for data visualization. In B. Preim, P. Rheingans, & H.Theisel,
Proceeedings of Eurographics Conference onVisualization (EuroVis) 2013.
http://idl.cs.washington.edu/papers/semantically-resonant-colors/
http://www.babynamewizard.com/voyager
Times to use color
•  When position is insufficient (lines crossing)
•  When it will aid pre-attentive processing
•  When it reinforces semantic content
•  When you want to encourage comparisons over
multiple figures
http://vallandingham.me/small_multiples_with_details.html
MORE ABOUT CHARTS
Data Visualization LibGuides
•  Data visualization:
http://guides.library.duke.edu/datavis
•  Visualization types:
http://guides.library.duke.edu/vis_types
•  Top 10 dos and don’ts for charts and graphs:
http://guides.library.duke.edu/topten
•  Visual communication:
http://guides.library.duke.edu/visualcomm
Good Chart Makeover Examples
The Why Axis chart remakes
http://thewhyaxis.info/remakes/
Storytelling With Data visual makeovers:
http://www.storytellingwithdata.com/search/
label/Visual%20Makeover
On the web
•  Bad examples:
WTF Viz, http://wtfviz.net/
•  Good examples:
Thumbs Up Viz, http://thumbsupviz.com/
•  Ask for help:
Help Me Viz, http://helpmeviz.com/
CONDUCTING VISUALIZATION RESEARCH
Types of Research
•  techniques
develop new
visual
metaphors
Speckmann, B., &Verbeek, K. (2010). Necklace maps. IEEE
Transactions onVisualization and Computer Graphics,16(6), 881-889.
http://dx.doi.org/10.1109/TVCG.2010.180
Types of Research
•  techniques
•  systems
develop new
software
Meyer, M., Munzner,T., & Pfister, H. (2009). MizBee:A
multiscale synteny browser. IEEETransactions onVisualization and
Computer Graphics,15(6), 897-904.
http://dx.doi.org/10.1109/TVCG.2009.167
Types of Research
•  techniques
•  systems
•  design studies
study how a specific
group or field uses
visualization Goodwin, S., Dykes, J., et al. (2013). Creative user-
centered visualization design for energy analysts and
modelers. IEEETransactions onVisualization and
Computer Graphics,19(12), 2516-2525.
http://dx.doi.org/10.1109/TVCG.2013.145
Types of Research
•  techniques
•  systems
•  design studies
•  evaluations
study how humans
generally interact
with visualizations
Ziemkiewicz, C., & Kosara, R. (2010). Laws of attraction:
From perceived forces to conceptual similarity. IEEE
Transactions on Visualization and Computer Graphics,16(6),
1009-1016.
http://dx.doi.org/10.1109/TVCG.2010.174
Types of Research
•  techniques
•  systems
•  design studies
•  evaluations
•  theories/models
develop a new theory of
visualization
Jansen,Y., & Dragicevic, P. (2013).An
interaction model for visualizations beyond
the desktop. IEEETransactions onVisualization
and Computer Graphics,19(12), 2396-2405.
http://dx.doi.org/10.1109/TVCG.2013.134
QUESTIONS? SUGGESTIONS?
angela.zoss@duke.edu
twitter.com/duke_vis
BONUS: COLOR THEMES FOR POSTERS,
INFOGRAPHICS, SLIDESHOWS, WEBSITES, ETC.
Theme
•  Pick two or three main colors that complement each
other to add visual interest
•  Maintain high visual contrast throughout
•  Do not use a background image
Design and Support Recommendations from Data Visualization Research
Design and Support Recommendations from Data Visualization Research
Design and Support Recommendations from Data Visualization Research
http://visual.ly/10-commandments-color-theory
BONUS: DEVELOPMENT OF A VIS PROJECT
http://bit.ly/pubmedvis
Changes over time?
Heat map
Changes over time?
Radial technique
Changes over time?
Line chart of ranks
Changes over time?
Stacked line
Changes over time?
Streamgraph
http://raw.densitydesign.org/
Design and Support Recommendations from Data Visualization Research
Correlations or flows
Alluvial diagram
http://raw.densitydesign.org/
Correlations or flows
Design and Support Recommendations from Data Visualization Research

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Design and Support Recommendations from Data Visualization Research

  • 1. Design and Support Recommendations from Data Visualization Research July 17, 2014 Science Boot Camp Southeast Raleigh, NC #BootCampSE14 Angela Zoss, @duke_vis Data Visualization Coordinator Duke University Libraries
  • 2. Using research to inform design Expert suggestions/heuristics http://bit.ly/tufte_vdqi http://bit.ly/bertin_sg http://bit.ly/few_smn
  • 3. Using research to inform design Empirical verification and elaboration http://bit.ly/cleveland_egd http://bit.ly/ware_iv http://bit.ly/wilk_gg
  • 4. Demo data for today http://bit.ly/bcse_zoss
  • 6. The research shows… •  Rotated text is harder to read Byrne, M. D. (2002). Reading vertical text: Rotated vs. marquee. In Proceedings of the Human Factors and Ergonomics Society 46th Annual Meeting; Santa Monica,CA. Human Factors and Ergonomics Society: 1633–1635. http://dx.doi.org/10.1177/154193120204601722
  • 7. The research shows… •  Rotated text is harder to read Byrne, M. D. (2002). Reading vertical text: Rotated vs. marquee. In Proceedings of the Human Factors and Ergonomics Society 46th Annual Meeting; Santa Monica,CA. Human Factors and Ergonomics Society: 1633–1635. http://dx.doi.org/10.1177/154193120204601722
  • 8. Text orientation State population from 2010 census http://en.wikipedia.org/wiki/US_states_by_population Easy in Excel
  • 9. Text orientation State population from 2010 census http://en.wikipedia.org/wiki/US_states_by_population Easy in Excel
  • 11. The research shows… •  Rotated text is harder to read •  People are very good at reading bar length, x/y position Vernier acuity:The ability to see if two line segments are collinear.Accurate to about 10 seconds of arc or 1/10 of a pixel. Ware, C. (2013). Information visualization:perception for design, third edition.Waltham, MA: Morgan Kaufmann Publishers. http://www.sciencedirect.com/science/book/9780123814647
  • 15. Perception of length/area Advanced in Excel http://peltiertech.com/Excel/Charts/DotPlot.html
  • 16. The research shows… •  Rotated text is harder to read •  People are very good at reading bar length, x/y position •  But even our positional acuity is no match for high data density
  • 17. Data density State population vs. Number of seats in U.S. House http://en.wikipedia.org/wiki/US_states_by_population Easy in Excel
  • 18. Data density State population vs. Number of seats in U.S. House http://en.wikipedia.org/wiki/US_states_by_population ? Easy in Excel
  • 19. Data density Fill transparency at 100% Easy in Excel
  • 20. Data density Fill transparency at 50% Easy in Excel
  • 21. Data density Both axes converted to logarithmic scale Easy in Excel
  • 22. Data density Ranges edited, vertical axis switched to base 2 Easy in Excel
  • 23. Data density Population mapped to horizontal axis, seats in house mapped to size, random “jitter” added as vertical axis values Intermediate in Excel
  • 24. The research shows… •  Rotated text is harder to read •  People are very good at reading bar length, x/y position •  But even our positional acuity is no match for high data density •  People are not as good at differentiating angles, areas Cleveland,W. S., & McGill, R. (1985). Graphical perception and graphical methods for analyzing scientific data. Science,299(4716), 828-833. http://dx.doi.org/10.1126/science.229.4716.828
  • 25. Angles, wedges, circles People are bad at comparing areas of shapes or judging certain relationships. If precision is important or data values are very similar, use bars or scatter plots. http://de.slideshare.net/vis4/making- data-visualizations-a-survival-guide/25 http://de.slideshare.net/vis4/making- data-visualizations-a-survival-guide/162 http://www.leancrew.com/all-this/2011/11/ i-hate-stacked-area-charts/
  • 26. Visual math http://eagereyes.org/criticism/visual-math-wrong If the chart makes it hard to understand an important relationship between variables, do the extra calculation and visualize that as well. http://bit.ly/SFeAwzhttp://bit.ly/PszKw0
  • 29. The research shows… •  People have trouble differentiating between more than 5-7 hues ? ? http://colorbrewer2.org/ Healey, C. G. (1996). Choosing effective colours for data visualization. In R.Yagel and G. M. Nielson (Eds.), Proceedings of the 7th conference onVisualization '96 (VIS '96), 263-270. http://dx.doi.org/10.1109/VISUAL.1996.568118
  • 30. Qualitative color classes With categorical/qualitative variables (e.g, states, genders, political parties), use at most 5-7 hues. States by population and house seats, colored by region Requires 4 separate data series Intermediate in Excel
  • 31. The research shows… •  People have trouble differentiating between more than 5-7 hues •  People have trouble differentiating between more than 5-7 shades http://colorbrewer2.org/ Gilmartin, P. and E. Shelton. (1990). Choropleth maps on high resolution CRTs:The effects of number of classes and hue on communication. Cartographica,26(2), 40-52. http://dx.doi.org/10.3138/W836-5K13-1432-4480
  • 32. Ordered color classes With classed/graduated variables (e.g., rating scores, age groups, any number that has been split into groups), use at most 5-7 shades. States by population and house seats, colored in 4 x-axis value groups Requires 4 separate data series Intermediate in Excel
  • 33. Continuous color With continuous variables (e.g., population, rainfall, timestamp), the only option in Excel is conditional formatting of cells. https://www.census.gov/hhes/migration/data/acs/state-to-state.html Migrations between states, colored continuously Easy in Excel
  • 34. Continuous color Depending on your data, a continues gradient might group too many elements into a small range of lightness. You can also transform the data (e.g., log) or create discrete classes for more control. Migrations between states, colored in 4 classes Requires conditional formatting “classic” rules for value ranges Intermediate in Excel
  • 35. The research shows… •  People have trouble differentiating between more than 5-7 hues •  People have trouble differentiating between more than 5-7 shades •  Rainbow color gradients are very problematic
  • 36. “Rainbow Color Map (Still) Considered Harmful” Borland, D., &Taylor, R.M. (2007). Rainbow color map (still) considered harmful. IEEE Computer Graphics and Applications,27(2), 14-17. http://dx.doi.org/10.1109/MCG.2007.323435
  • 37. Perceptual ordering. (a) We can easily place the gray paint chips in order based on perception, (b) but cannot do this with the colored chips. Borland & Taylor (2007) Confusing
  • 38. Spatial contrast sensitivity function. We can see detail at much lower contrast in the (a) luminance-varying gray-scale image than with the (b) rainbow color map. Borland & Taylor (2007) Obscuring
  • 39. Four data sets visualized with (a) rainbow, (b) gray-scale, (c) black-body radiation Apparent sharp gradients in the data in (a) are revealed as rainbow color map artifacts... The sharp gradient found at the center of the second data set... is not found in the corresponding image with the rainbow color map. Borland & Taylor (2007) Actively misleading
  • 40. Related: Salience Rainbows also cause salience problems; some colors in the inner part of the rainbow “pop out” more than colors at the extremes. http://dx.doi.org/10.1038/nmeth.1762 http://mycarta.wordpress.com/ 2012/12/21/comparing-color-palettes/
  • 41. Instead of rainbows… Solution: Use a single hue, varying luminance If you want color to show a numerical value, use a range that goes from white to a highly saturated color in one of the universal color categories. http://shar.es/CfbSd http://www.flickr.com/photos/sadrzy/4154089647/
  • 42. ColorBrewer Cynthia Brewer, PhD – Penn State http://colorbrewer2.org/
  • 43. The research shows… •  People have trouble differentiating between more than 5-7 hues •  People have trouble differentiating between more than 5-7 shades •  Rainbow color gradients are very problematic •  For highest contrast, limit colors and vary luminance
  • 44. Color versus position Do you really need color at all? Intermediate in Excel
  • 45. Color versus position Do you really need color at all? Intermediate in Excel
  • 46. Color versus position Do you really need color at all? Easy* in Excel *Creating charts with manually-selected y values is easy and very useful. Adding labels, though, can be harder. Sometimes it’s easiest to add them manually.
  • 47. Visual contrast If you use color sparingly, you can save it for contrast. Intermediate in Excel
  • 48. Visual contrast Contrast is important to direct attention and improve clarity. It can also shield against projection/printing issues or color interference effects. http://shar.es/CWktB
  • 49. Times to use color
  • 50. Times to use color •  When position is insufficient (lines crossing) as opposed to: http://vis4.net/blog/posts/doing-the-line-charts-right/
  • 51. Times to use color •  When position is insufficient (lines crossing) •  When it will aid pre-attentive processing Count the 4s. 173658103837575063348181736401016254 539319123938525616173943987139874619 319586716628309897273164613984019358 094285976205897629835921873589321759 871059283198254781237598698127359812!
  • 52. Times to use color •  When position is insufficient (lines crossing) •  When it will aid pre-attentive processing 173658103837575063348181736401016254 539319123938525616173943987139874619 319586716628309897273164613984019358 094285976205897629835921873589321759 871059283198254781237598698127359812! Count the 4s.
  • 53. Times to use color •  When position is insufficient (lines crossing) •  When it will aid pre-attentive processing •  When it reinforces semantic content Lin, S., Fortuna, J., et al. (2013). Selecting semantically-resonant colors for data visualization. In B. Preim, P. Rheingans, & H.Theisel, Proceeedings of Eurographics Conference onVisualization (EuroVis) 2013. http://idl.cs.washington.edu/papers/semantically-resonant-colors/ http://www.babynamewizard.com/voyager
  • 54. Times to use color •  When position is insufficient (lines crossing) •  When it will aid pre-attentive processing •  When it reinforces semantic content •  When you want to encourage comparisons over multiple figures http://vallandingham.me/small_multiples_with_details.html
  • 56. Data Visualization LibGuides •  Data visualization: http://guides.library.duke.edu/datavis •  Visualization types: http://guides.library.duke.edu/vis_types •  Top 10 dos and don’ts for charts and graphs: http://guides.library.duke.edu/topten •  Visual communication: http://guides.library.duke.edu/visualcomm
  • 57. Good Chart Makeover Examples The Why Axis chart remakes http://thewhyaxis.info/remakes/ Storytelling With Data visual makeovers: http://www.storytellingwithdata.com/search/ label/Visual%20Makeover
  • 58. On the web •  Bad examples: WTF Viz, http://wtfviz.net/ •  Good examples: Thumbs Up Viz, http://thumbsupviz.com/ •  Ask for help: Help Me Viz, http://helpmeviz.com/
  • 60. Types of Research •  techniques develop new visual metaphors Speckmann, B., &Verbeek, K. (2010). Necklace maps. IEEE Transactions onVisualization and Computer Graphics,16(6), 881-889. http://dx.doi.org/10.1109/TVCG.2010.180
  • 61. Types of Research •  techniques •  systems develop new software Meyer, M., Munzner,T., & Pfister, H. (2009). MizBee:A multiscale synteny browser. IEEETransactions onVisualization and Computer Graphics,15(6), 897-904. http://dx.doi.org/10.1109/TVCG.2009.167
  • 62. Types of Research •  techniques •  systems •  design studies study how a specific group or field uses visualization Goodwin, S., Dykes, J., et al. (2013). Creative user- centered visualization design for energy analysts and modelers. IEEETransactions onVisualization and Computer Graphics,19(12), 2516-2525. http://dx.doi.org/10.1109/TVCG.2013.145
  • 63. Types of Research •  techniques •  systems •  design studies •  evaluations study how humans generally interact with visualizations Ziemkiewicz, C., & Kosara, R. (2010). Laws of attraction: From perceived forces to conceptual similarity. IEEE Transactions on Visualization and Computer Graphics,16(6), 1009-1016. http://dx.doi.org/10.1109/TVCG.2010.174
  • 64. Types of Research •  techniques •  systems •  design studies •  evaluations •  theories/models develop a new theory of visualization Jansen,Y., & Dragicevic, P. (2013).An interaction model for visualizations beyond the desktop. IEEETransactions onVisualization and Computer Graphics,19(12), 2396-2405. http://dx.doi.org/10.1109/TVCG.2013.134
  • 66. BONUS: COLOR THEMES FOR POSTERS, INFOGRAPHICS, SLIDESHOWS, WEBSITES, ETC.
  • 67. Theme •  Pick two or three main colors that complement each other to add visual interest •  Maintain high visual contrast throughout •  Do not use a background image
  • 72. BONUS: DEVELOPMENT OF A VIS PROJECT
  • 76. Changes over time? Line chart of ranks
  • 80. Correlations or flows Alluvial diagram http://raw.densitydesign.org/