Visualization Design

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Visualization Design

• cs5984 Information Visualization
• Chris North

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Spotfire
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Simple Visualization Model
Data
View Port
Visual Mapping
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Data Table
Attributes

• Types
• Quantitative
• Ordinal
• Nominal/Categorical

Items (aka cases, tuples, data points, )
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Visual Mapping

• Define a Space
• Map data ? marks
• Map data attributes ? graphical mark attributes
• Year ? X
• Length ? Y
• Popularity ? size
• Subject ? color
• Award? ? shape

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Ranking Visual Attributes

• Position
• Length
• Angle, Slope
• Size
• Color

Increased accuracy for quantitative
data -Cleveland
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Visualization Design Process

• Primary Inputs
• Data
• User Task
• Compare, known item search, patterns, outliers,
• Scale
• items
• dimensionality
• User characteristics
• Standards/guidelines
• System resources

• Bag of tricks
• View types
• Interaction strategies

Design
Visualization
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Design Principles

• 5 HCI Metrics
• User performance
• Error rate
• User satisfaction
• Learning time
• retention

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Interactivity

• Interaction to handle increased scale
• Direct Manipulation
• Visual representation
• Rapid, incremental, reversible actions
• Pointing instead of typing
• Immediate, continuous feedback
• Encourage exploration

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Increase Data Density

• Calculate data/pixel

A pixel is a terrible thing to waste.
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Eliminate Chart Junk

• How much ink is used for non-data?
• Reclaim empty space ( screen empty)
• Attempt simplicity(e.g. am I using 3djust for
  coolness?)

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Information Visualization Mantra

• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• Overview first, zoom and filter, then details on
  demand
• E.g. Spotfire

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Query Previews

• http//www.cs.umd.edu/egemen/demo.html

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Data Space

• Multi-dimensional databases,
• 1D timelines,
• 2D maps,
• 3D volumes,
• Hierarchies/Trees directories,
• Networks/Graphs web, communications,
• Document collections digital libraries,

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Assignment

• Read for Tues
• Inselberg Multidimensional detective (parallel
  coordinates) book p107 (margaret, josh s)
• Kandogan Star Coordinates web (matt c,
  fanye)
• Read for Thurs
• Rao Table Lens p343,597 (marty e, purvi)
• Feiner Worlds within Worlds p96 (scott m, ?)
• Find some interesting data
• Send me your picture