SIMS 247: Information Visualization and Presentation jeffrey heer

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SIMS 247 Information Visualization and
Presentationjeffrey heer
Tree Visualization Oct 26, 2005    
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today

• administrivia
• tree visualization
• design exercise

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administrivia

• How are project proposals coming along?
• If you have questions, concerns, or are seeking
  advice, come to my office hours!!
• Today, 1-230pm - 210 South Hall
• Appointments also possible

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Graphs and Trees

• Graphs
• Representations of structured, connected data
• Consist of a set of nodes (data) and a set of
  edges (relations)
• Trees
• Graphs with a specific structure
• connected graph with n-1 edges
• Representations of data with natural hierarchy
• Nodes are either parents or children

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Tree Visualization

• File Hierarchyin computer
• Need to navigate through the hierarchy to find a
  particular file
• Two common problems Where am I? and Where is
  the file that I am looking for?

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Tree Visualization

• Organizational Chart

http//www.cs.umd.edu/hcil/spacetree/

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Tree Visualization

• Tournaments

taken from To Draw A Tree by Pat Hanrahan
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Tree Visualization

• Family Trees

taken from To Draw A Tree by Pat Hanrahan
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Tree Visualization

• Family Trees

taken from To Draw A Tree by Pat Hanrahan
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Tree Visualization

• Evolutionary Trees

taken from To Draw A Tree by Pat Hanrahan
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Tree Visualization

• Evolutionary Trees

taken from To Draw A Tree by Pat Hanrahan
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Tree Visualization

• Assembly Instructions

taken from To Draw A Tree by Pat Hanrahan
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Tree Visualization Approaches

• Node-Link Diagrams
• Reingold-Tilford Layout
• Radial Layout
• Indented Layout
• Cone Trees Balloon Trees
• Hyperbolic Trees
• Enclosure Diagrams
• TreeMaps
• Voronoi TreeMaps
• Jigsaw Maps
• Alternative Approaches
• Icicle Trees
• Sunburst Diagrams
• Cascaded Lists

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Reingold-Tilford Layout
Top-down layout Uses separate dimensions for
breadth and depth breadth --gt width depth --gt
height
tidier drawing of trees - reingold, tilford
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Radial Layout
Places children on increasing larger radii A
top-down layout converted into polar
co-ordinates breadth --gt angle depth --gt
radius
gnutellavision yee, fisher, dhamija, hearst
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Indented Layout
Places all items along vertically spaced
rows Uses indentation to show parent child
relationships Breadth and depth end up fighting
for space resources breadth --gt height, locality
depth --gt height, indentation
microsoft file explorer
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Cone Trees
Top-down tree layout in three dimensions Shadows
provide 2D structure Can also make Balloon
Trees 2D version of ConeTree
cone tree robertson, mackinlay, and card
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Balloon Trees

• flattened cone trees

herman, melancon, and marshall
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Hyperbolic Trees
Places nodes using hyperbolic geometry This is
then projected into normal space
hyperbolic tree lamping, rao
h3 viewer tamara munzner
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TreeMaps
Space-filling technique that divides space
recursively Segments space according to size of
children nodes
map of the market wattenberg / smartmoney.com
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Voronoi TreeMaps
voronoi treemaps - balzer and deussen

• TreeMaps that divide space using arbitrary
  polygons based on Voronoi tesselations.

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Jigsaw Maps
jigsaw maps - martin wattenberg

• Space-filling technique from Martin Wattenberg -
  a mathematical experiment at trying to achieve a
  perfect layout.
• Uses the mathematics of space-filling curves.

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Icicle Trees

• Edges implied by adjacency and spatial
  relationship.

icicle tree in the infovis toolkit - jean-daniel
fekete
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Sunburst Diagrams

• Radial version of icicle trees.

sunburst diagram - john stasko
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Cascaded Lists

• Display one selected group of silbings at a time
• Mac OS X File System Browser

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More advanced trees

• We can augment the approaches weve seen so far
  with additional visualization and interaction
  techniques. Some examples
• Degree-of-Interest Trees / SpaceTree
• top-down node-link diagrams with focuscontext
• Elastic Hierarchies
• node-link diagrams crossed with treemaps
• Dual Trees
• bi-directional top-down node-link diagrams
• developed for genealogical graphs

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degree-of-interest trees
doitrees - heer, card
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elastic hierarchies

• hybrid of node-link diagrams and treemaps

elastic hierarchies - zhao, mcguffin, chignell
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dual-trees

• a bidirectional tree visualization designed for
  navigating genealogical graphs (family trees)

dual-trees - mcguffin, balakrishnan
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So what technique to use?

• A cautionary tale
• CHI Browse-off and evaluation of the hyperbolic
  tree
• What makes the difference the car or the driver?
• Reading
• People read faster by scanning in lines (not
  arcs!)
• Convention
• Does your application domain have established
  conventions? How can you leverage or augment
  those?
• Designs with multiple visual components
• How much screen real-estate do you give the tree?
• (Sometimes that indented tree works the best!)

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Design Exercise

• Brainstorm new visualizations for family trees
• Choose an aspect NOT covered by current designs
• Here are some of the complications to consider
• People as individuals / Couples as reproductive
  units
• Ordering by Generation vs. Time
• Divorce/Death/Remarriage
• Polygamy
• Incest (!)
• Social vs. Biological lineages?
• Think of important questions a visualization
  should answer, use them to motivate the design
• Are two people related? In how many ways?
• Work in groups of 3 or more. You will be asked to
  briefly present your ideas to the class on Monday!

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