2.2 data and information
- 1. INFO 2Unit 2.2 Data and Information
- 3. What is Data?What types of data are there?What is a BitWhat is a ByteWhat is a KilobyteTo consolidate you should be able to answer these questions…
- 5. In today’s lesson we are going to continue learning about binaryObjectives
- 6. Data is raw facts and figures or a set of values, data has no meaning.Examination Results (DATA) : 3312, 2, 35, 3, 64, 4421, 2, 48, 3, 56Data is generated by an event e.g. Buying a product in a supermarketLoyalty card numberBarcode number of each item boughtWeight of applesCredit card number to pay for goodsWhat is Data?
- 7. Data can arise in formats other than numbers and textText (Alphanumeric)Number (Numeric)BooleanAudioImageVideoWhatever the type of data bring input, computers store and process data using binary numbers.Types of data
- 8. What is data capture?Means the collection of data to enter into a computerHow can we enter data into a computer?KeyboardSpeech recognitionWebcam Touch screenScannerBar code readerSensors How data can arise
- 9. Direct Data CaptureCollection of data for a particular purposeDirect Data Capture MethodsBar Code ReaderMICROMROCRSensorsDirect and Indirect data capture
- 10. Indirect Data CaptureCollection of data as a by-product from another purposeExampleUsing the data collected from reading barcodes at a super market till to work out stock levelsDirect and Indirect data capture
- 11. GIGOIn ICT GIGO stands for Garbage In Garbage OutIt relates to Information only being as good as the data that is inputi.e. I put incorrect data into a system (accidently or deliberately) then the information that is output will be incorrect.Use only a Pencil, one key colour and an A4 piece of paper to illustrate this Abbreviation and it’s meaning. Think about using a diagram, keywords and definitions to illustrate.Activity
- 12. Encoding is used by computers to convert the data into machine readable form i.e. binaryEncoding Data
- 13. A single unit in binary is called a ‘bit’ (stands for binary digit)Computer memory is measured in ‘bytes’Onebyte is made up of eightbitsOne byte can store one character e.g. the letter A is represented by 010000001Binary Numbers
- 14. One byte can store one character e.g. the letter A is represented by 010000001Another variation of this byte can store another Character e.g. B is represented by 01000010A byte has 256 variations of data it can storeBinary Numbers
- 15. Protocols have been developed to standardize the conversion of this binary code to content we are familiar with.ASCII is a standard that converts binary to character outputMP3 is a standard that converts binary to audio outputProtocols
- 17. The American Standard Code for Information InterchangeDefines 128 characters (Requires only 7 bits of a byte)ASCII
- 18. We can work out the binary from the decimal and vice versa, the decimal from the binaryASCII
- 19. Binary to DecimalSimply plot the 1’s under the necessary values e.g. if I want 67ASCIIC
- 20. ASCIIDecimal to Binary is a little trickierLets imagine you want to find the binary for decimal 116 (The letter t)You must work your way through the table belowCan you take 128 from 116?NO (0)Can you take 64 from 116?YES (1) you now have 52Can you take 32 from 52?YES (1) you now have 20Can you take 16 from 20?YES (1) you now have 4Can you take 8 from 4?NO(0) you still have 4Can you take 4 from 4?YES(1) you now have 0Can you take 2 from 0?NO(0) you still have 0Can you take 1 from 0?NO(0) you still have 001110100
- 21. Use the two methods you have just learnt to convert the following:Binary to Decimal01001101 = 10011111 = 01100000 =00010100 =Decimal to Binary48 = 239 = 110 = 17 =Activity
- 22. Use the two methods you have just learnt to convert the following:Binary to Decimal01001101 = 7710011111 = 15901100000 =9600010100 = 20Decimal to Binary48 = 00110000239 = 11101111110 = 0110111017 = 00010001Activity
- 23. Coding data is NOT the same as Encoding dataData is coded to reduce data entry and reduce the need for storage space.Imagine this scenario:You are conducting 500,000 questionnairesYou ask each user to identify whether they are male or femaleThe largest response would be ‘female’ which contains 6 bytes of dataIf all 500,000 users are female that means that the total storage for that one response will be:3000,000 bytes2929 Kilobytes2.8 MegabytesIf you were to code this data by asking the user are you M/FThe largest response would be M or F which both contain only one byteThis would reduce the data storage to:500,000 bytes488 Kilobytes0.47 MegabytesCoding data
- 24. Examples of data that are coded are:Gender often asked as M or FBank sort codes are a number (60-55-63) instead of the name of the branchDates of Birth instead of 18th February 1981 it becomes 18/02/81Destinations at Airports DXB, LHR etc.PostcodesCodes are used because:Can be easier to remember (ISBN’s are not)Usually short and quicker to enter (thus fewer errors are likely to be made)Take up less storage spaceEnsure consistencyEasier to check that the data is validWho codes data and why?If the data is to become information it is likely that the data is decoded before it is output e.g. barcode (coded data) output information – total cost of product
- 25. Loss of precisionExamplesHow old are you? 12 – 15 16 – 18 19 – 23How would you rate this school? Poor Good Very Good (Value judgement is required here also)The colour of the article will beProblems with coding data
- 26. What is Processing?It is the work the computer does on the data to convert it into information e.g. searching, calculating, sorting etc.Processing
- 27. What is information?Information is data that has been processed, put into context and given a meaning. It must be understandable to the user.Information
- 28. Information is good quality if it is:AccurateUp-to-dateCompleteFrom a reliable sourceRelevantQuality of information
- 29. How accurate will depend upon its use:Bank statement details should be exact to the pennyWhole School A Level pass rates at a school might be to the nearest 1% (This would be sufficient)Imagine inaccurate information relating to stock figures this could result in products not being available to customers or an over order resulting in to much stock to store.Thorough error checking and regular up dates must take place to ensure the information is as accurate as possibleAccurate Informationhttp://news.bbc.co.uk/2/hi/8176957.stm
- 30. Some information only has value within a specific time scale e.g. share prices.If information is out of date wrong decisions could be made. For example:An employee of a cinema taking a booking for the evening performance needs to know which seats are available at the time of booking not the ones available at the start of the day.Reports should contain dates and where possible timesKeeping data up-to-date effects the costsUse to be batch processing now transaction processingUp-To-Date Information
- 31. If information is incomplete it loses its value and can misinform. If you collect details about a householder for insurance purposes and don’t request information about the value of the house, the house might be insured for the wrong value.If you conduct a survey and half of the questions are not answered your analysis of those results could be inaccurate.Complete Informationhttp://www.bbc.co.uk/news/business-10701953
- 32. The internet offers a huge range of information. However, the internet is not governed, thus no one controls the content.Consider Wikipedia, it is an open source network that allows anyone who is registered to add content. There are editors who are able to check the validity but only to the extent of their knowledge base.Trusted sites like .gov .ae, BBC are recommendedInformation from a reliable source
- 33. Information is only valuable to someone who has use for it and its value will depend on its potential use.RelevantObama’s views on the value of information, is it just a distraction?http://tek.io/hwJAiP
- 34. Global Positioning Systems (GPS)Are able to provide drivers with accurate, relevant and Up-to-Date InformationGPS
- 35. How does social media impact the quality and value of information?Consider this Cairo activists comments: “We use Facebook to schedule the protests, Twitter to coordinate, and YouTube to tell the world."Discussionhttp://www.bbc.co.uk/news/world-africa-12289475