CS 171: Visualization Design Principles Hanspeter Pfister pfi[email protected] Last Time Visualization

To convey information through graphical representations of data Due This Week

• HW0, including course survey (due tonight) • Readings week 1: A. Cairo and T. Munzner Design Critique

NYT, 2008 Print Edition Last.fm Listening History

Harvard Business Review

June 2010, HBR by Jeff Clark Design Design “Design must be functional and functionality must be translated into visual aesthetics, without any reliance on gimmicks that have to be explained.” F. A. Porsche Graphical Design Design Excellence “Clutter and confusion are not attributes of information, they are failures of design.” E. Tufte Edward Tufte Outline • Graphical Integrity • Visualization Design Principles • Graphic Design Principles Graphical Integrity Missing Scales

($11,410)

($4,200,000)

Tufte, VDQI Scale Distortions

Nielson Scale Distortions

Flowing Data Scale Distortions

Flowing Data Scale Distortions

A. Kriebel, VizWiz Scale Distortions Scale Distortions Scale Distortions Scale Distortions Global Warming?

The Daily Mail, UK, Jan 2012 Global Warming?

Mother Jones Global Warming!

Mother Jones The Lie Factor Size of effect shown in graphic Size of effect in data

Tufte, VDQI The Lie Factor

Tufte, VDQI

U.S. SmartPhone Marketshare

21.2%

39.0% RIM 3.1% Apple Palm 7.4% Motorola Nokia 9.8% Other 19.5% U.S. SmartPhone Marketshare

21.2%

RIM Apple 39.0% Palm 3.1% Motorola Nokia 7.4% Other

9.8%

19.5% U.S. SmartPhone Marketshare

40% 39.0

30%

20% 21.2 19.5

10% 9.8 7.4

3.1 0% RIM Other Apple Palm Motorola Nokia Tufte’s Integrity Principles

• Clear, detailed, and thorough labeling and appropriate scales • Size of the graphic effect should be directly proportional to the numerical quantities (“lie factor”) • Show data variation, not design variation Visualization Design Principles Maximize Data-Ink Ratio

Data ink Data-Ink Ratio = Total ink used in graphic

700

525

350

175 Males 0 Females

0-$24,999 $25,000+ 0-$24,999 $25,000+ Maximize Data-Ink Ratio

Data ink Data-Ink Ratio = Total ink used in graphic

700

525

350

175

0 Males Females

0-$24,999 $25,000+ 0-$24,999 $25,000+ Avoid Chartjunk Extraneous visual elements that distract from the message

ongoing, Tim Brey Avoid Chartjunk

ongoing, Tim Brey Avoid Chartjunk

ongoing, Tim Brey Avoid Chartjunk

ongoing, Tim Brey Avoid Chartjunk

ongoing, Tim Brey Avoid Chartjunk

ongoing, Tim Brey Increase Data Density Number data items Data density = Area of data in graphic

Ho et al., “Thermal Conductivity of the Elements: A Comprehensive Review” J. Phys. Chem. 1974 A. Cairo, The Functional Art M. Novotny and H. Hauser, “Outlier-Preserving Focus+Context Visualization in Parallel Coordinates,” IEEE Transactions on Visualization and Computer Graphics, 2006. Steve Chappel and Reebe Garofalo in Rock 'N' Roll is Here to Pay: The History and Politics of the Music Industry, 1977 Tufte’s Design Principles

• Maximize data-ink ratio • Avoid chart junk • Increase data density • Layer information

Subjective Dimensions

• Aesthetics: Attractive things are perceived as more useful than unattractive ones • Style: Communicates brand, process, who the designer is • Playfulness: Encourages experimentation and exploration • Vividness: Can make a visualization more memorable

Pat Hanrahan, Nov 2007 Graphic Design Principles Robin Williams Contrast Repetition Alignment Proximity

Robin Williams Contrast Repetition Alignment Proximity

Robin Williams Principle of Contrast

If two items are not exactly the same, then make them different. Really different. Don’t be a wimp. A. Cairo, The Functional Art M. Meyer D3, M. Bostock R. Kosara, S. Miksch, and H. Hauser, “Focus+Context Taken Literally,” IEEE Computer Graphics and Applications, 2002. Contrast Repetition Alignment Proximity

Robin Williams Principle of Repetition

Repeat some aspects of the design throughout the entire piece Small Multiples

D3, M. Bostock A. Gelmann M. Meyer, B. Wong, M. Styczynski and H. Pfister. “Pathline: A Tool For Comparative Functional Genomics”, Computer Graphics Forum, 2010 Contrast Repetition Alignment Proximity

Robin Williams Principle of Alignment

Nothing should be placed on the page arbitrarily

Every item should have a visual connection with something else D3, M. Bostock M. Meyer, B. Wong, M. Styczynski and H. Pfister. “Pathline: A Tool For Comparative Functional Genomics”, Computer Graphics Forum, 2010 C. Partl, A. Lex, M. Streit, D. Kalkofen, K. Kashofer, and D. Schmalstieg, “enRoute: Dynamic Path Extraction from Biological Pathway Maps for In-Depth Experimental Data Analysis,” IEEE Symposium on Biological Data Visualization, 2012 Contrast Repetition Alignment Proximity

Robin Williams Principle of Proximity

Group related items together . . . as physical closeness implies a relationship Proximity

Protovis, M. Bostock M. Meyer, T. Munzner, A. DePace, H. Pfister, “MulteeSum: A Tool for Comparative Spatial and Temporal Gene Expression Data”, IEEE Transactions on Visualization and Computer Graphics, 2010 M. Dörk, S. Carpendale, and C. Williamson, “Visualizing explicit and implicit relations of complex information spaces,” Information Visualization, 2012 Contrast Repetition Alignment Proximity

Robin Williams Further Reading Stephen Few Graph Design IQ Test

Stephen Few, Perceptual Edge Garr Reynolds Next Week • HW1(due Thursday) • Bring laptops on Tuesday (Intro to Python) • Readings: Carpendale and Cleveland / McGill