1. November 6-9, Seattle, WA Bad Reports: Fixing Their Mistakes Roger Noble Consultant LobsterPot Solutions

2. My bad report NSW Police report Just an example, not really from the NSW Police Dept. (source data.gov.au)data.gov.au Report is used to: Track incident response times Incident rates across divisions Incident rates by offence 2 BID-210

3. November 6-9, Seattle, WA Bad Report Demo 3

4. First Some Theory What are we trying to communicate? Remove non-data pixels and chartjunk Increase data density Use colour sparingly 4 BID-210

5. Data ink and non-data ink 5 BID-210

6. Chartjunk 6 = 38.7% BID-210

7. Colour 7 BID-210

8. Data-Ink Ratio 8 BID-210 Ink used to present the data Total ink used

9. Process for continual improvement 9 1.Identify non-data pixels a.Can it be removed? b.Can it be deemphasised? 2.Identify data pixels a.Is it meaningful? b.Can it be emphasised? 3.Repeat BID-210

10. November 6-9, Seattle, WA Let’s fix it! Demo 10

11. Charts 11 BID-210

12. Charts 12 BID-210

13. Charts 13 BID-210

14. Data types 14 Dimensions NominalLocation OrdinalDays of week IntervalTime Measures AdditiveSales amount Non-additiveTemperature BID-210

15. Data types - Charting 15 Dimensions Measures Nominal Ordinal Interval Additive Non-additive Measures Additive Non-additive BID-210

16. Charting – Line vs Bar 16 BID-210 Nominal

17. Charting – Line vs Bar 17 BID-210 Nominal

18. Charting – Line vs Bar 18 BID-210 Interval

19. Charting – Line vs Bar 19 BID-210 Interval

20. November 6-9, Seattle, WA Let’s fix it! Demo 20

21. Tables 21 BID-210

22. Tables Remove unnecessary colour and gridlines 22 BID-210

23. Tables Remove gridlines and unnecessary colour 23 BID-210

24. Tables Add lines and emphasis where necessary 24 BID-210

25. Tables Add white space to aid with reading 25 BID-210

26. Tables Add white space to aid with reading White space allows the eye to easily scan down columns and across rows 26 BID-210

27. Indicators Be optimistic add indications only for exceptions 27 BID-210

28. Indicators Be optimistic add indications only for exceptions 28 BID-210

29. November 6-9, Seattle, WA Let’s fix it! Demo 29

30. Problems with Pie charts Requires mental conversion from size/angle to percentage. Works well when values are close to 25% and 50% (90 o and 180 o ) 30 BID-210

31. Problems with Pie charts Distortion from perspective Slices that are closer appear larger than they are 31 BID-210

32. Problems with Pie charts Actual values can be listed in a smaller space (higher data-ink ratio) 32 = 1.32% (40) 2.24% (30) 3.20% (25) 4.24% (30) BID-210

33. Problems with Pie charts Patterns are harder to perceive 33 BID-210 VS

34. Area based charts Area is difficult to quantify Bubbles must be sized by area not diameter (or radius or circumference) 34 Incorrect Sized by diameter Correct Sized by area BID-210 N2N

35. What else is bad? 35 Size can be perceived differently based on surroundings BID-210

36. November 6-9, Seattle, WA Let’s fix it! Demo 36

37. Summary 37 Identify key information Improve the data-ink ratio (remove chartjunk) Use whitespace to aid in scanning rows and columns Be optimistic with indicators Only use area based charts when accuracy isn’t important BID-210

38. Recommended Reading 38 Edward Tufte Steven Few Also: William S. Cleveland, Colin Ware, Nathan Yau and Benjamin Willers BID-210

39. November 6-9, Seattle, WA 39 Thank you for attending this session and the 2012 PASS Summit in Seattle