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i247: Information Visualization and PresentationMarti Hearst

Types of Graphs and VisualizationsJanuary 28, 2008

 

 

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Course Goals

Students will be able to:

– Describe the key design guidelines and techniques for visual display of information, including the relationship to human perception.

– Design interactive visualizations to support thought, understanding, and insight, using real data.

– Explore and critically evaluate visualization techniques and applications.

Adapted from Stone & Zellweger

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What are your course goals?

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Types of Symbolic Displays (Kosslyn 89)

• Graphs

• Charts

• Maps

• Diagrams

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T yp e n am e h e reT yp e t it le h e re

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Types of Symbolic Displays• Graphs

– at least two scales required– values associated by a symmetric “paired with”

relation• Examples: scatter-plot, bar-chart, layer-graph

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Types of Symbolic Displays

• Charts– discrete relations among discrete entities– structure relates entities to one another– lines and relative position serve as links

• Examples:– Family tree– Flow chart– Network diagram

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Types of Symbolic Displays• Maps

– Internal relations determined (in part) by the spatial relations of what is pictured

– Labels paired with locations

• Examples:– Map of census data– Topographic maps

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Types of Symbolic Displays

• Diagrams– Schematic pictures of objects or entities– Parts are symbolic (unlike photographs)

• how-to illustrations• figures in a manual

From Glietman, Henry. Psychology. W.W. Norton and Company, Inc. New York, 1995

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What is the “real” taxonomy for visual representations?

• An empirical investigation by Lohse et al.’94– (Only used static, 2D graphics)– 16 participants

• Half had a graphic design background– First, looked at 60 images and scored them along 10

scales.• These were used to compute statistical similarity

– Then, organized the 60 images into categories according to similarity.

• Were asked to name the groups• Then they grouped these into higher-level groups, repeatedly,

until they were in one large group.

Lohse, G L; Biolsi, K; Walker, N and H H Rueter, A Classification of Visual Representations,

CACM, Vol. 37, No. 12, pp 36-49, 1994

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Scales that Participants Used(and percentage of variance explained)

16.0 emphasizes whole – parts11.3 spatial – nonspatial10.6 static structure – dynamic structure10.5 continuous – discrete10.3 attractive – unattractive10.1 nontemporal – temporal 9.9 concrete – abstract 9.6 hard to understand – easy 9.5 nonnumeric – numeric 2.2 conveys a lot of info – conveys little

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Resulting Categories (Lohse et al. 94)

• Graphs• Tables (numerical)• Tables (graphical)• Charts (time)• Charts (network)• Diagrams (structure)• Diagrams (network)• Maps• Cartograms• Icons• Photo-realistic images

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Graphs

• Encode quantitative information using position and magnitude of geometric objects.

• Examples: scatter plots, bar charts.

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Tables• An arrangement of words, numbers, signs, or

combinations of them to exhibit a set of facts or relationships in a compact fashion.

• Less abstract symbolic notation than graphs.– Graphical tables and numerical tables

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Time Charts

• Display temporal data.– Gantt chart, time schedule.

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Network Charts• Show the relationships among components• Symbols indicate the presence or absence of

components. • Correspondences are shown by lines, arrows,

proximity, similarity, or containment.– Flow charts, org charts, pert charts, decision trees.

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Structure Diagrams

• A static description of a physical object.• Spatial layout expresses true coordinate

dimensions of the object.– Cross-sections

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Process Diagrams• Describe interrelationships and processes

associated with physical objects.• Spatial layout expresses dynamic, continuous,

or temporal relationships among the objects.– Lifecycle

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Maps

• Symbolic representations of physical geography.– Marine charts, topo maps, projections of world maps.

• Differ from cartograms in that cartograms super-impose quantitative data over a base map.

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Cartograms

• Spatial maps that show quantitative data.• Show more quantitative information than

structure diagrams.– Chloropleths, dot maps, flow maps.

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Icons

• Impart a single interpretation or meaning for a picture; a unique label for a visual representation.

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Photo-realistic Pictures

• Realistic images of an object or scene.

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Put into Multiple Categories

• No real agreement on these.

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Where should these go?

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Other Findings (Lohse et al. 94)

• Photorealistic images were least informative– Echos results in icon studies – better to use less complex,

more schematic images

• Graphs and tables are the most self-similar categories– Results in the literature comparing these are inconclusive

• Cartograms were hard to understand– Echos other results – better to put points into a framed

rectangle to aid spatial perception

• Temporal data more difficult to show than cyclic data– Recommend using animation for temporal data

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In honor of UCB’s FTN Effort This Thursday

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The NYTimes Illustrates Climate Change

• Cartoon• Illustrative Photograph• Graph• Graph (multiple views)• Interactive Graphs• Combination of Photo Illustration, Drawn

Illustration, Information Graphics• Video

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The NYTimes Illustrates Climate Change

• Cartoon– Carbon Neutral Confession– April 28, 2007– Ron Barrett– NYTimes– http://www.nytimes.com/2007/04/29/weekinreview/29revkin.html?

scp=11&sq=global+warming&st=nyt

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The NYTimes Illustrates Climate Change

• Illustrative Photograph– A Disaster Epic (in Slo-Mo)– February 4, 2007– Macdiarmid/Getty Images– http://www.nytimes.com/2007/02/04/weekinreview/04basic.html?

scp=9&sq=global+warming&st=nyt

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The NYTimes Illustrates Climate Change

• Information Visualization Graphic– Carbon Dioxide in the

atmosphere– April 23, 2006– Bill Marsh– NYTimes– http://www.nytimes.com/

imagepages/2006/04/23/weekinreview/20060423revkin_graphic.html

– http://www.nytimes.com/2006/04/23/weekinreview/23revkin.html

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The NYTimes Illustrates Climate Change

• Static Graphic (Multiple Views)– Far Down the List of Worries– (from the story Yelling 'Fire' on a Hot

Planet by Revkin)– April 23, 2006– NYTimes– Bill Marsh– http://www.nytimes.com/imagepages/

2006/04/23/weekinreview/20060423revkin2_graph.html

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The NYTimes Illustrates Climate Change

• Combination: Photo Illustration, Drawn Illustration, Information Graphics– A Battle Between the Bottle and the

Tap– July 15, 2007– Bill Marsh, Tony Cenicola– Satisfying the National Thirst ... With

Lots of Bottles– http://www.nytimes.com/2007/07/15/weekinreview/

15marsh.html?scp=54&sq=global+warming&st=nyt

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The NYTimes Illustrates Climate Change

• Graphic– A Carbon Tide: Past, Present, and

Future– Bill Marsh– December 16, 2007– NYTimes– http://www.nytimes.com/interactive/2007/12/16/

weekinreview/20071216_EMISSIONS_GRAPHIC.html

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The NYTimes Illustrates Climate Change

• Interactive flash graphics– October 1, 2007– Sea Ice in Retreat– Aigner, Corum, Nguyen– NYTimes– http://www.nytimes.com/interactive/2007/10/01/

science/20071002_ARCTIC_GRAPHIC.html– http://topics.nytimes.com/top/news/science/

topics/globalwarming/index.html

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The NYTimes Illustrates Climate Change

• Video– Solar City: A Co-op Goes

Green– January 23, 2008– Dwyer, Romero, Witty– NY Times– http://video.on.nytimes.com/?

fr_story=aa81e9284c77f01e48353c64b86fa7a0a21e887f