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This overview discusses various strategies for creating effective information visualizations by leveraging different visual representations, such as hierarchies, networks, and multi-dimensional data. The focus is on design principles that enhance user experience, including employing techniques like zooming, bifocal views, and semantic zooming to address challenges like the Keyhole Problem. Empirical evaluations of these approaches demonstrate improved user performance and satisfaction. This resource serves as a guide for developing visual overviews that facilitate exploration and understanding across diverse data sets.
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Visual Overview Strategies cs5984: Information Visualization Chris North
Multi-D 1D 2D 3D Hierarchies/Trees Networks/Graphs Document collections Design Principles Empirical Evaluation Java Development Visual Overviews Multiple Views Where are we?
Quiz • 4 focus+context strategies: • bifocal • Perspective • Wide-angle lens • bubble
Why Overviews? Data Screen a a data data a data data
Advantages of Overviews 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, Leung, Plaisant, Chimera, North, etc.
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, Overview+Detail, Focus+Context
Data Scale Attribute 2 Attribute 1 (9,9) (5,7) (3,2) • Small scale data = easy • Just show everything • But, there’s always more data… • How much can you show?
Overview Strategies for Large Scale • Screen: Reduce visual representation size • Pack more on the screen • Data: Reduce data scale • Use less data to fit screen Data Screen
1. Reduce Visual Representation “Hammer” Data Screen
Reduce Visual Representation • Stasko, “Information Mural” • Ben, Ahmed
2. Reduce Data Scale “Chainsaw” Data Screen
Data Scale • Reduce data scale to fit screen • Reduce # attributes • Reduce # items • Reduce value “size” • 2 Approaches: • Eliminate • Aggregate
Reduce # Attributes • Eliminate attributes • Scatterplot: selects 2 attributes, ignores rest • Aggregate attributes • Column math: grade = (hw1 + hw2) / 2 • Star Coordinates: vector summaps n attributes to 2 (x,y) • Multi-dimensional scaling:statistical technique to map n-D to 1,2,3-D usingdistance between points
Reduce # Items • Eliminate items • VIDA (Visual Info Density Adjuster): show high priority items (video) • Human-Eye View: focused info density • Aggregate items • Group many items into one • SQL “group by” • Snap-Together Visualization: drill down (1:M) • Aggregate Towers • Semantic zooming, Abstraction • Pad++, Jazz
Aggregation with Zooming • Rayson, “Aggregate Towers” • Anil, Supriya
Summary • Reduce visual representation (Hammer) • Reduce data scale (Chainsaw) • Eliminate • Aggregate
DataWear • Umer Farooq • IEEE InfoVis 2001
Assignment • Thurs: Multiple View Strategies • Chi, “Visualization Spreadsheet” • mudita, abhi • North, “Snap-Together Visualization” • varun, kumar
Next Week • Tues: Trees • Rao, “Hyperbolic Trees” • david, harsha • Robertson, “Cone Trees” • anuj, atul • Thurs: Trees • Johnson, “Treemaps” • vishal, jeevak • Beaudoin, “Cheops” • jon, mudita
Homework #3 • See website for important details • Due Tues Oct 23 • Zoomable visualization design • Use Jazz HiNote to create an information space • Topic ideas: hobby, life story, event, academic field • Goal: help someone learn about topic • 1 page report: analysis of zooming concept, your design • Be creative, have fun! • http://vtopus.cs.vt.edu/~north/infoviz/hinoteapplet.html