SpaceTree: Supporting Exploration in Large
Node Link Tree, Design Evolution and Empirical
Evaluation
Catherine Plaisant, Jesse Grosjean, Benjamin B.Bederson
in Proceedings of IEEE Symposium on Information Visualization,
2002: 57 -64, Boston, October 2002
Presented by
Mei Huang & Chunyuan Liao
3/10, 2005
Outline
Motivation
Related work
Highlights of SpaceTree
Controlled Experiments
Comments
Discussions
Motivation
Improve classic tree representation (node
link diagram) by zoomable UI and
animation techniques



Classic representation is the most familiar
mapping of a tree
Inefficient space usage makes large tree
exploration not so convenient
Zooming & animation can improve user
experiences
Related work (1)
Category 1 : Space filling

Representatives
Treemaps
Information slices

Comments
Focus on leaf nodes, not the tree topology
Users need training due to unfamiliarity
Information Slices
Related work (2)
Category 2 : Node link

Techniques
Layout :

V/H hierarchy, Circular layout (hyperbolic tree), 3D diagram
Uneven scaling :

Overview + Detail views, Zooming, Pruning, Expand & Contract
Selective rendering :


Dynamic Query
Comments
Clearer and intuitive view of tree topology
Challenge in screen space usage
Highlights & Early Design lessons
Semantic zooming
Aggressive expanding
Decomposed tree animation
Landmark
Search & Filter
Demo
Hyperbolic Browser
Lay a whole tree out in
a hyperbolic plane and
map it to a unit disk
Focus & context
Smooth & continuous
animation
Circle Limit IV by M.C. Escher
Demo
John Lamping, Ramana Rao, and Peter Pirolli “A Focus+Context Technique Based on
Hyperbolic Geometry for Visualizing Large Hierarchies” Processdings of the ACM SIGCHI
Conference on Human Factors in Computing Systems, Denver, May 1995
Comparing SpaceTree, Hyperbolic Tree Browser,
MS Explorer, and Treemap
Task
type
Node
location
Visiting
history
Topology
question
Task examples
Applications
ST
HT
Ep
TM
Find max/min on some attribute
-
-
-
+
Find a specific node by title
+
+
-
+
Locate visited nodes
-
-
-
-
Quick overview
+
+
-
-
Compare 2+ branches
-
-
-
-
List ancestors
+
-
-
-
Find braches with 10+ children
-
+
-
-
Compare branch size
+
-
-
-
Compare subtree depth
+
-
-
-
Comments
A good application of zoomable UI & animation
Early version review provides very useful
information
Controlled experiments were carefully designed;
observation explanations were clear and sound
Screen space usage could be improved
Discussions
Checking available space in both
dimensions?
Alternative summarizers
Label several previously visited paths may
be useful
How to deal with large node bounding box?
Combining ST with HT?