Edward Tufte s Principles & Guidelines of Information Design

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1 Edward Tufte s Principles & Guidelines of Information Design A framework for thinking about Information Design Haig Armen harmen@ecuad.ca

2 I do not paint things, I paint only the differences between things Henri Matisse Paris, 1943

3 Edward Tufte Tufte (pronounced TUFF-tee) defies easy categorization. His academic training and work at Stanford, Princeton, and Yale span statistics, computer science, political economy, and design. Tufte s fame all flows from a rethinking of information design. He has consulted with IBM, helped The New York Times redo its information graphics, advised NASA and recently been hired by Obama.

4 Tufte Books The Visual Display of Quantitative Data Visual Explanations Envisioning Information Beautiful Evidence

5 Principles of Information Design Guidelines for Information Design Micro/Macro Readings

6 Principles of Information Design 1. Comparisons 2. Causality 3. Multivariate Analysis 4. Integration of Evidence 5. Documentation

7 Principle 1: Comparisons The fundamental analytical act in statistical reasoning is to answer the question Compared to what? Whether we are evaluating changes over space or time, plotting out variables, the essential point is to make intelligent and appropriate comparisons.

8 Comparison of World Rivers and Mountains Without the various sequences of lakes, linearly arranged, this information design becomes just another bar chart. Source: Edward R. Tufte, Envisioning Information, pp.77 Illustration: Joseph Hutchins Colton, Johnson s New Illustrated Family Atlas with Physical Geography (New York 1864), pp

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10 Source: Edward R. Tufte, Envisioning Information, pp.31 Illustration: United States v. Gotti, et al., 1987 Chart supplied by counsel, Bruce Cutler and Susan G. Kellman A Graphic You Can t Refuse: Mobster John Gotti s attorneys used this graphic (detail) in 1987 to show the jury the criminal history of the witnesses against their client. The chart helped illuminate a major weakness in the case against Gotti. Visual displays of information encourage a diversity of individual viewer styles and rates of editing, personalizing, reasoning, and understanding.

11 Principle 2: Causality Visual displays of information should present both cause and affect. Explaining the data helps viewers see the relevance in the information. In what way are you trying to assist thinking What is the thinking task?

12 Finding the Cause of Cholera When cholera deaths were plotted on a map, they showed a close link between the disease and a Broad Street water pump. Source: Edward R. Tufte, Visual Explanations: Images and Quantities, Evidence and Narrative, pp.27 31

13 Illustrating Danger The designer of this graphic responded to information provided by the (U.S.) National Park Service, after witnessing a drowning at this very river. Source: Edward R. Tufte, Visual Explanations: Images and Quantities,Evidence and Narrative, pp.144 Illustration: Johnstone Quinan, The Washington Post June 9, 1985

14 The Ultimate Weed Rather than simply being an inventory of parts, this design portrays verbs and nouns. This design blends words and images into a memorable account. Real details combine to form a coherent picture of an imagined plant. Source: Edward R. Tufte, Visual Explanations: Images and Quantities, Evidence and Narrative, pp.126 Illustration: Patricia Wynne, Scientific American July, 1991

15 Principle 3: Multivariant Analysis Although many information graphics are presented on two dimensions, they can successfully present multiple variables to help provide context and relevance.

16 The Fate of Napoleon s Army Six variables are plotted in this rich, coherent story: the size of the army, its location on a two-dimensional surface, direction of the army s movement, and temperature on various dates during the retreat from Moscow. Source: Edward R. Tufte, The Visual Display of Quantitative Information, pp.41 Illustration: Charles Joseph Minarde, Tableaux Graphiques et CDartes Figuratives de M. Minard

17 Principle 4: Integration of Evidence Displays of data are rarely presented without the integration of words. Using proximity to connect relevant explainations to graphics provides a subtle understandable way to illustrate complex storylines.

18 Visual Hierarchy in Information Design When everything is emphasized (background, structure, content), nothing is emphasized; the design will often be noisy, cluttered, and informationally flat. Source: Edward R. Tufte, Visual Explanations: Images and Quantities, Evidence and Narrative, pp.74

19 Learning Typographical Details Codes obstruct parallelism; replacing codes with direct labels unifies the information. Source: Edward R. Tufte, Visual Explanations: Images and Quantities, Evidence and Narrative, pp.98 99

20 How big is that cloud? Fundamentals of scale, orientation, and labels are often missing in the colourful images emanating from computer visualizations. Tufte s redesign locates the storm within a 3-dimensional tripod of scales and directional arrows. Source: Edward R. Tufte, Visual Explanations: Images and Quantities, Evidence and Narrative, pp.20 21

21 Principle 5: Documentation The credibility of a presentation depends significantly on the quantity and integrity of the authors and their data sources. Documentation is an essential mechanism of quality control for displays of evidence. Thus authors must be named, sources described, scales labeled, details enumerated.

22 Guidelines for Information Design 1. Use a narrative quality ( find a story to tell about the data) 2. Implement visual layering and separation to reduce noise and enrich the content. 3. Avoid Chart Junk - content-free decoration 4. When differentiating, use the smallest effective difference

23 Life Cycle of the Japanese Beetle This information design simultaneously describes two dimensions, space and time, on the horizontal while maintaining a vertical spatial dimension. Source: Edward R. Tufte, Envisioning Information, pp.110

24 Letterform comparison In the original diagrams (left) three A s are filled in and seven are not, creating two distinct and meaningless visual clusters. Redrawn (right) with all letterforms filled in places all letterforms in a common environment more suitable for comparison. Source: Edward R. Tufte, Visual Explanations: Images and Quantities, Evidence and Narrative, pp.112

25 Chart Junk This data-thin chart mixes up changes in the value of money with changes in diamond prices, a crucial confusion because the graph chronicles a time of high inflation. Source: Edward R. Tufte, Envisioning Information,pp.77 Illustration: Joseph Hutchins Colton, Johnson s New Illustrated Family Atlas with Physical Geography (New York 1864)

26 More Chart Junk In the worst graphic ever to find its way into print, five colours report only five pieces of data (the division within each year adds to 100 percent). Lurking behind chart junk is contempt both for information and for the audience. Cosmetic decoration will never salvage an underlying lack of content. Source: Edward R. Tufte, The Visual Display of Quantitative Information, pp.118

27 Marshalling Signals In the information prison (top), grid, silhouette, and type compete at the same nervous level. Too loud and too similar. To direct attention toward the information at hand, the revision extends the light to dark range of colour, separating and layering the data in proportion to their relevance. Source: Edward R. Tufte, Envisioning Information, pp.63

28 Micro / Macro Readings The most elegant representations of data illuminate information on both focused details as well as higher levels of persepective.

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