1. cs5984: Information Visualization Chris North
Visualization Design
cs5984: Information Visualization
Chris North

2. Spotfire

3. Simple Visualization Model
Data
View Port
Visual Mapping

4. Data Table Attributes Items (aka: cases, tuples, data points, …)
Types:
Quantitative
Ordinal
Nominal/Categorical
Items
(aka: cases, tuples, data points, …)

5. Visual Mapping Define a Space Map: data  marks
Map: data attributes  graphical mark attributes
Year  X
Length  Y
Popularity  size
Subject  color
Award?  shape

6. Ranking Visual Attributes
Position
Length
Angle, Slope
Size
Color
Increased accuracy for quantitative data
-Cleveland

7. Visualization Design Process
Primary Inputs:
Data
User Task
Compare, known item search, patterns, outliers,…
Scale
# items
dimensionality
User characteristics
Standards/guidelines
System resources
Bag of tricks:
View types
Interaction strategies
Design
Visualization

8. Design Principles 5 HCI Metrics: User performance *** Error rate
User satisfaction
Learning time
retention

9. Interactivity Interaction to handle increased scale
Direct Manipulation
Visual representation
Rapid, incremental, reversible actions
Pointing instead of typing
Immediate, continuous feedback
Encourage exploration

10. Increase Data Density Calculate data/pixel
“A pixel is a terrible thing to waste.”

11. Eliminate “Chart Junk”
How much “ink” is used for non-data?
Reclaim empty space (% screen empty)
Attempt simplicity (e.g. am I using 3d just for coolness?)

12. Information Visualization Mantra
Overview first, zoom and filter, then details on demand
E.g. Spotfire

13. Query Previews

14. Data Space Multi-dimensional: databases,… 1D: timelines,… 2D: maps,…
3D: volumes,…
Hierarchies/Trees: directories,…
Networks/Graphs: web, communications,…
Document collections: digital libraries,…

15. Assignment Read for Tues: Read for Thurs: Find some interesting data
Inselberg “Multidimensional detective” (parallel coordinates) book p107 (margaret, josh s)
Kandogan “Star Coordinates” web (matt c, fanye)
Read for Thurs:
Rao “Table Lens” p343, (marty e, purvi)
Feiner “Worlds within Worlds” p96 (scott m, ?)
Find some interesting data
Send me your picture