Introduction to Information Visualization

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Introduction toInformation Visualization

• John Stasko
• Georgia Institute of Technology

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Exercise

• House directions

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Data Explosion

• Society is more complex
• There simply is more stuff
• Computers, internet and web give people access to
  an incredible amount of data
• news, sports, financial, purchases, etc...

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How much data?

• Between 1 and 2 exabytes of unique info produced
  per year
• 1000000000000000000 (1018) bytes
• 250 meg for every man, woman and child
• Printed documents only .003 of total

Peter Lyman and Hal Varian, 2000 Cal-Berkeley,
Info Mgmt Systems www.sims.berkeley.edu/how-much
-info
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Data Overload

• Confound How to make use of the data
• How do we make sense of the data?
• How do we harness this data in decision-making
  processes?
• How do we avoid being overwhelmed?

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The Problem
Web,Books,Papers, Game scores, Scientific
data, Biotech, Shopping People Stock/finance News

Data
Data Transfer
How?
Vision 100 MB/s Ears lt100 b/s Telepathy Haptic
/tactile Smell Taste
Two slides courtesyof Chris North
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Human Vision

• Highest bandwidth sense
• Fast, parallel
• Pattern recognition
• Pre-attentive
• Extends memory and cognitive capacity
• People think visually
• Impressive. Lets use it!

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Example
Which state has the highest income? Is there a
relationship between income and education? Are
there any outliers?
Questions
Example courtesyof Chris North
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Visualize the Data
College Degree
Per Capita Income
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Even Tougher?

• What if you could only see 1 states data at a
  time? (e.g. Census Bureaus website)
• What if I read the data to you?

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Exercise Redux

• An interesting query
• People work differently

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Our Challenge

• Transform the data into information
  (understanding, insight) thus making it useful to
  people

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Visualization

• Often thought of as process of making a graphic
  or an image
• Really is a cognitive process
• Form a mental image of something
• Internalize an understanding
• The purpose of visualization is insight, not
  pictures
• Insight discovery, decision making, explanation

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Main Idea

• Visuals help us think
• Provide a frame of reference, a temporary storage
  area
• Seeing is believing
• A picture is worth a thousand words
• External cognition
• Role of external world in thinking and reason
• An illustrative example
• Can you think of more?

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Overview
VisualizationData visualization
Scientificvisualization
Informationvisualization
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Scientific Visualization

• Primarily relates to and represents something
  physical or geometric
• Often 3-D
• Examples
• Air flow over a wing
• Stresses on a girder
• Torrents inside a tornado
• Organs in the human body
• Molecular bonding

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Information Visualization

• What is information?
• Items, entities, things which do not have a
  direct physical correspondence
• Notion of abstractness of the entities is
  important too
• Examples baseball statistics, stock trends,
  connections between criminals, query results,
  java programs, ...

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Information Visualization

• What is visualization?
• The use of computer-supported, interactive visual
  representations of data to amplify cognition.
• From Card, Mackinlay Shneiderman 98

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Information Visualization

• Components
• Taking items without a direct physical
  correspondence and mapping them to a 2-D or 3-D
  physical space.
• Giving information a visual representation that
  is useful for analysis and decision-making

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Two Key Attributes

• Scale
• Challenge often arises when data sets become very
  large
• Interactivity
• Want to show multiple different perspectives on
  the data

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Domains for Info Vis

• Statistics
• Text
• Financial/business data
• Internet information
• Software
• ...

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Examples

• Images
• Are these static pictures information
  visualizations?

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Excel
Get rid ofthose darn 3Dbars!
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USA Today Graphics
Or worse yet
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Atlanta Flight Traffic
Atlanta Journal April 30, 2000
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In LivingColor
Maxim Magazine, July 01
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Country Music
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The Comics
UnderstandingComics by Scott McCloud
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Unemployment Rates
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SARS Outbreak
www.cdc.gov/mmwr/preview/mmwrhtml/mm5212a1.htm
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London Subway
www.thetube.com
Harry Beck
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True Geography
www.kottke.org/plus/misc/images/tubegeo.gif
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Easy Walking Lines Added
rodcorp.typepad.com/photos/art_2003/tube_walklines
_final_lmfaint.html
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Napoleans March
From E. Tufte The Visual Display of Quantitative
Information
size of army direction
latitude longitude
temperature date
Minard graphic
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NYC Weather
2220 numbers
Tufte, Vol. 1
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Examples

• Software

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Map of the Market
www.smartmoney.com/marketmap
Demo
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Ishkurs Electr. Music Guide
www.ishkur.com/music/
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StarTree
Hyperbolic tree
www.inxight.com
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Tasks in Info Vis

• Search
• Finding a specific piece of information
• How many games did the Braves win in 1995?
• What novels did Ian Fleming author?
• Browsing
• Look over or inspect something in a more casual
  manner, seek interesting information
• How did the Falcons season go last year?
• Whats a good car to buy?

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Tasks in Info Vis

• Analysis
• Comparison-Difference
• Outliers, Extremes
• Patterns
• Assimilation
• Monitoring
• Awareness
• Presentation

More to come in a future class
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End