Visual Overview Strategies

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Visual Overview Strategies

• cs5984 Information Visualization
• Chris North

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Homework 1

• Grading , ?, -, 0
• Tablelens
• Shows all attributes simultaneously (overview)
• Sorting relates 1 attribute ? Many attributes
• Spotfire
• multiple representations (scatter, 3D, bar,
  histo, )
• details-on-demand better than Tablelens FC
• - scatterplot 2D occlusion problem
• Scatter relates 1 attribute ? 1 attribute
• Strategy
• First Tablelens for overview
• Then Spotfire for detail analysis

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Visual Overview Design Goals

• Visual take advantage of human visual
  processing
• Information Rich show as much as you can!
  (while maintaining a clean design)
• Interaction Affordances enable quick access to
  details
• E.g. Zooming, OverviewDetail, FocusContext

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Visual Overview Advantages

• Helps solve the Keyhole Problem
• 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, error
  rates, retention, satisfaction
• Studies, e.g. Beard Walker, Chimera, North,
  etc.

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Strategy

• Strategy 1 Display everything!
• Only works for small scale
• Strategy 2 Reduce scale to fit screen
• Reduce items
• Reduce attributes
• Reduce value size

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Strategies

• Filtering
• Aggregation / Abstraction
• Reduced Representation

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Filtering

• Filter attributes
• Scatterplot selects 2 attributes, ignores rest
• Filter items
• VIDA (Visual Info Density Adjuster) show high
  priority items, representative set (video)
• Human-Eye View focused info density

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Aggregation

• Aggregate items
• Grouping several items into one (e.g. SQL group
  by)
• Snap-Together Visualization overviewdetail,
  drill down
• Semantic zooming
• Pad (Abstraction)
• Lifelines?
• NetViz
• Aggregate attributes
• Star Coordinates

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Reduced Representation

• Stasko, Information Mural, web
• sanjini, luhui

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Assignment - Trees

• Read for Tues
• Rao, Hyperbolic Tree, book pg 382
• Joy, maulik
• Kumar, Multi-level DQ and Pruning, book pg 295
• Read for Thurs
• Johnson, Treemaps, book pg 152
• Stasko, Sunburst, web
• Marcus, marty
• Project groups meet with me early next week

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Homework 2

• Due Thurs March 1 (1 week)
• Visualization Design
• Visualizing timed paths
• (the bus schedule problem!)