1. Usability Case Study: Datamaps Visualization
Chris North
CS 3724: HCI

2. DataMaps DataMaps http://infovis.cs.vt.edu/census/Datamaps.htm
Color map
Select for detail table
Histo Sliders filter
Plot brushing
Sticky note help

3. Usability Videos Succeeded at easy task
Sticky Help sometimes useful, terminology tricky
Problems:
Map navigation, want to go ‘back’
Click instead of drag sliders
Think histogram is barchart, each bar is a state?
Never colored map
Never used plot
How to find other data fields (More Variables)
Filtering mis-interpreted
Stuck in table, not using visualization

4. Re-design Ideas Users familiar with data ‘table’ concept
Variables (population,…)
States
Table-first approach
All variables accessible via treeview (Win Explr)
Data shown for selected states
Entice users to visualization
Pop-up when click variable
“drop here”

5. Wizard of Oz New table design successful
“drop here” failed (drop what here?)
Should group map and histo for an attribute
Wiz-of-Oz hard with dynamic visualization!

6. Histo Slider Re-design
Designs:
Smooth curve (black), instead of bars
Selection range (yellow), selection curve (red)
Brushing (direct selection in histo) vs sliders
Slider thumb variations
On, above, below
Squares, triangles
Between thumbs: bar, button, circle
Text input boxes, range
Results:
Smooth curve successful, understood ‘humps’
Brushing used, sliders not used
Brushing: clicked first, but eventually drag
Text boxes good, but can override vis.

7. Clean Design Rob Miller, MIT: visually integrated design
Brad Paley, Didi / Columbia: eliminate typical windows paraphernalia

8. Other… Moving users from table to visualization Progressive usage
Post-it help
Histogram design, interaction
Brushing instead of filtering, single interaction model

9. Fun: Verbal-visual conflict

10. Fun: How to Lie with Visualization

11. The hidden 0-points
Lie factor = ?