2. Gregory Bateson (1904-1980)
British anthropologist, social scientist, linguist, visual
anthropologist, semiotician and cyberneticist whose work intersected
that of many other fields
Major books:
Steps To An Ecology of the Mind, 1972
Mind and Nature: A Necessary Unity, 1979
3. Information and Mind
All information is communicated as differences
The mind operates with hierarchies and networks to create gestalten.
Hierarchies are nested containers
Networks are links connecting discrete nodes
Information architecture is
the re/shaping of information/differences into hierarchies and networks
we search for and visualize the patterns that connect
The pattern that connects is the pathways for accessing differences
4. Jacques Bertin (1918-2010)
Visual Variables for Quantitative Information
“Matrix theory of graphics,” Information Design Journal,
Vol. 10, No. 1. (2002)
Semiology of graphics: Diagrams, Networks, Maps
(Univ of Wisconsin, 1983; ESRI, 2010)
originally published as Sémiologie graphique (1967)
6. 6
Variables of the Image (1-3)
• X/Y Position
• Size: Z value of quantity (area) superimposed on position
• Value: Z value of content (fill) superimposed on position
16. 16
Color Use Guidelines for Data Representation
Brewer, C. A. 1999. Color Use Guidelines for Data Representation, Proceedings of
the Section on Statistical Graphics, American Statistical Association
17. 17
Online resources
Brewer, C. A. 1999. Color Use Guidelines for Data
Representation, Proceedings of the Section on
Statistical Graphics, American Statistical
Association
http://www.personal.psu.edu/cab38/ColorSch/ASApaper
.html
No more excuses: a list of references to learn how
to use color
http://diuf.unifr.ch/people/bertinie/visuale/2009/0
5/infovis_color_theory_in_few_li.html
22. 22
Don’t make me think
Immediate Visual Scan Repeated Visual
Scan
An interaction is intuitive
when the user makes the least effort to grasp the
difference.
23. 23
Steps of Visual Cognition
Preattentive
Perception Cognition
Processing
Perception
• All based on changes in contrast: hue, brightness, and color
palette
• We detect differences, physiologically and psychologically
Pre-attentive Processing
• Processed in under 250 milliseconds (Healey, Booth, and Enns, 1995)
• Parallel (bottom-up) processing
Cognition
• Serial (top-down) processing
24. 24
Elementary Perceptual Tasks
We are good at some tasks,
but not others
• Good at: position, length,
direction
• Bad at: area (of a circle),
volume, saturation
This is why you will see
line or bar graphs to
convey data
• You will never (well, shouldn’t)
see a graph that uses color
saturation to convey data (i.e.
using different shades of
orange)
25. 25
Preattentive Processing
Second step of visual perception
“The perception of a pattern can often
• Sits between perception and cognition
be the basis of a new insight.”
• Processed in under 250 milliseconds
- Colin Ware, Information Visualization
• Understanding without training or cognition
• Serial vs. parallel processing
• Forms objects in the mind’s eye
Preattentive variables
• Proximity, similarity, connectedness, continuity, symmetry, closure, relative size,
figure and ground, intensity, curvature,
line length, color, orientation, brightness, and direction of movement.
• Overlapping variables
• Many theories as to how we deal with these – Feature Integration Theory, for one (2
variables at most)
Variable hierarchy
