1. cs5984: Information Visualization Chris North
Trees 2
cs5984: Information Visualization
Chris North

2. 2 Approaches Connection (node & link) Containment (node in node)
Outliner, …
Containment (node in node)
Venn diagram
Structure vs. attributes
Attributes only (multi-dimensional viz)
Structure only (1 attribute, e.g. name)
Structure + attributes A B C
today A B C

3. 3D

4. Treemaps Shneiderman, “Treemaps” Vishal, Jeevak Maryland
Maryland

5. Treemap Algorithm Calculate node sizes:
Recurse to children
node size = sum children sizes
Draw Treemap (node, space, direction)
Draw node rectangle in space
Alternate direction (slice or dice)
For each child:
Calculate child space as % of node space using size and direction
Draw Treemap (child, child space, direction)

6. Squared Treemaps
Wattenberg
Van Wijk

8. Cushion Treemaps
Van Wijk

9. Dynamic Queries

10. Treemaps on the Web
Map of the Market:
People Map:
Coffee Map:

11. DiskMapper

12. Sunburst
Stasko, GaTech
Radial layout
Animated zooming

13. Sunburst vs. Treemap + Faster learning time: like pie chart
+ Details outward, instead of inward
+ Focus+context zooming
- Not space filling
- More space used by non-leaves
All leaves on 1-D space, perimeter
Treemap: 2-D space for leaves
- Smaller scale?

14. CHEOPS Beaudoin, “Cheops” Jon, Mudita

15. Summary
Hyperbolic
ConeTree
TreeMap
Sunburst
Cheops

16. The Original Fisheye View
George Furnas, 1981 (pg 311)
Large information space
User controlled focus point
How to render items?
Normal View: just pick items nearby
Fisheye View: pick items based on degree of interest
Degree of Interest = function of distance from f and a priori importance
DOI(x) = -dist(x,f) + imp(x) f x

17. Example: Tree structure
Distance = # links between f and x
Importance = level of x in tree
Distance: I A a i ii b B
Importance: I A a i ii b B
DOI: I A a i ii b B f

20. Next Week I will be away Book chapter 6 Tues: Dr. McCrickard
Healey, “Preattentive Processing”
parool, priya
Somervell, “InfoVis in the Periphery”
ali, vikrant
Thurs: Virtual Environments
Go directly to Torg 3050
Dr. Bowman, Alex Kalita

21. Next Next Week Tues: Networks Thurs: Networks
Eick, “SeeNet”
kuljit, anil
Munzner, “H3: 3D hyperbolic graphs”
dananjan, samil
Thurs: Networks
Korn, “Multi-Digraphs”
ying, kuljit
Storey, “SHriMP”
qing, quoc
Tues Oct 30: Project status report due
Thurs Nov 1: Homework #3 due
Purvi: HiNote info session, Fri 4pm, McB 655
Change!