1. Information Visualization 2: Overview and Navigation
Chris North
cs3724: HCI

2. Review
Shneiderman’s Info. Vis. mantra?
Mapping data to graphics?

3. The Problem
Data
Screen

4. Typical Navigation
1D scrollbar 2D scrollbars
What’s
wrong?

5. Keyhole Problem Where am I? Where can I go? Where do I want to go?
How do I get there?
Lack of context, overview

6. Keyhole Problem

7. Context is Important!

8. E.g: 3 Overviews of Text
(MS Word)
Advantages?

9. Visual Overview Show me the data!
Map, organization (spatial layout of concepts)
What information is (not) available?
Adds context info, relationships
Enables direct access
Encourages exploration
HCI metrics:
Improves user performance, learning time, satisfaction
Insight

10. Navigation Strategies
Detail Only
Overview+Detail
Multiple views
Zooming
Focus+Context
Distortion, fisheye

11. Zooming large 2D spaces Powers of 10

12. Zooming: 2D KidPad, HiNote, Jazz http://www.cs.umd.edu/hcil/jazz/
Semantic zooming:
Don’t just show things at different size
change objects to make sense
E.g. add/remove detail info
Powers of Ten
Controls?

13. Overview+Detail: 1D
SeeSoft

14. Overview+Detail: 2D Overview: Detail: Zoom factor = 5
Square in overview tightly-coupled to scroll bars of detail

15. Multiple levels = large scale
overview
intermediate view
intermediate view
detail view
Zoom factor = 125

16. Multiple Foci
Linkit

17. Focus+Context: 1D
Fisheye Menu:
Perspective Wall

18. Focus+Context: 2D

19. Comparison
Zooming:
Overview+Detail:
Focus+Context:

20. Comparison Zooming: Overview+Detail: Focus+Context:
Screen space efficient
Infinite scalability
Lose overview when zoom in
Overview+Detail:
Good scalability, chaining
Multiple foci
Disconnect between views, back-n-forth
Focus+Context:
Integrated overview with detail, connected
Least scalable
Distortion, overview unstable

21. Quiz
Spotfire?
TableLens?

22. Design Exercise