Tree-Maps
A Space-Filling Approach to the Visualization
of Hierarchical Information Structures
Brian Johnson
l
Ben Shneiderman
Cyntrica Eaton
February 11, 2001
Sneak Peek
Sneak Peek
A
B
D
C
E
F
B
C
D
Overview
Part I: Tree-Maps
•
Introduction
•
Traditional Data Display
•
Tree Maps
•
Contributions
Overview
Part II: Paper Characteristics
•
Critique
•
Favorite Sentence
•
References
•
Current State
Part I
Introduction
•
Hierarchical Data
•
Organization Charts
•
Family Trees
•
Animal Phyla
•
Library Catalogs
• Visualizations display relationships among data
• Effective data presentation has posed a problem
Introduction
Hierarchical Data Presentation:
• Text-Based
I.
A.
B.
•
C.
Connection
1.
2.
a.
b.
c.
D.
E.
F.
•
Enclosure
a.
b.
II.
c.
A.
B.
C.
Introduction
Hierarchical Data Presentation:
• Text-Based
•
Connection
A
B
D
C
E
•
Enclosure
F
Introduction
Hierarchical Data Presentation:
• Text-Based
•
Connection
•
Enclosure
B
C
D
Connection
A
B
• Contain structural information and node content
D
C
E
• Generally easy to lay out and interpret
F
• Excellent visualization tools for small data sets
Exploit human ability to quickly recognize l
relationships among entities based on
l
spatial configuration.
Connection
A
B
• As data set gets larger, the information space l
l gets harder to see
- Amount of information shown can be far
l less than user is capable of processing
D
C
E
- User becomes more responsible for l l l l
l recalling information and tree node location
F
• Node-link diagrams contain great deal of
e empty space
Motivation
Objective:
l
To produce a compact visualization of a directory
tree structure
Expected Benefits:
• View large file directories in a constrained space
• Locate large files quickly and easily
• Determine which users consume more disk space
File Directory
File Directory
Tree Diagram
Desktop
My Documents
My Computer
….
Recycle Bin
….
ACL60
………… …………
DFS
Lexicon
Grammar
….
BFS
Allegro
Venn Diagram
Desktop
My Docs
My Comp
My Ntwk
ACL60
Recycle Bin
Tree-Map
My Doc
My Comp
Recycle
My Ntwk
ACL60
Tree-Maps
• Use entire information space
• Effective for showing quantitative properties of data
• Interactivity allows users to become more connected with l
l data display
Tree Diagram
Desktop
My Documents
My Computer
….
Recycle Bin
….
ACL60
………… …………
DFS
Lexicon
Grammar
….
BFS
Allegro
Tree-Map
My Doc
My Comp
Recycle
My Ntwk
ACL60
Tree-Map Construction
A
B
D
C
E
F
Node
Weight
A
10
B
1
C
4
D
5
E
2
F
3
Tree-Map Construction
A
B
D
C
A: 10
E
F
B: 1 C: 4
D: 5
E: 2 F: 3
Tree-Map Construction
A
B
D
C
A
E
F
Tree-Map Construction
A
B
D
C
E
F
B
C
D
Tree-Map Construction
A
B
D
C
E
F
B
C
D
Contribution
Introduces a method of enclosure to allow human
visualization of large amounts of hierarchical data
in a constrained information space.
Part II
Critique
Strengths:
•
Concise
•
Well developed
Weakness:
Had to read it a couple of times to get a full
understanding of how tree-maps are constructed
Favorite Sentence
The Tree-Map visualization technique makes 100% use of
the available display space, mapping the full hierarchy onto
a rectangular region in a space-filling manner.
References
Tree Maps: A Space-Filling Approach to the
Visualization of Hierarchical Information Structures
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Data Visualization
• Human ability to grasp
l graphical information
• Color Coding
• Similar studies
References
Tree Maps: A Space-Filling Approach to the
Visualization of Hierarchical Information Structures
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Data Visualization
• Offspring work
• Visual mapping techniques
• Hierarchical information
l display
Current State
Applications:
•
Disk Mapper
•
NBA Statistics
•
Stock Portfolio Visualization
•
PhotoMesa
NBA Statistics
NBA
Atlantic
…………………….
Central
Midwest
Pacific
……………
…………………
Lakers
Suns
……………
Kings
NBA Statistics
Stock Portfolio
PhotoMesa
Current State
Research:
• Incorporating even larger data sets and allowing them to be readable
• Supporting data animation
• Creating better data views
Current State
Conclusion
Efficient Space Utilization:
Great for large information structures
Interactivity:
User control in the presentation of data
Comprehension:
l
Rapid extraction of information with low perceptual
and cognitive loads
Aesthetics:
Visually pleasing rendering of data