Information Visualization (Part 1) cs3724: HCI

The Problem Data Human Data Transfer Goal: Insight How?

Human Vision Highest bandwidth sense Fast, parallel Pattern recognition Pre-attentive Extends memory and cognitive capacity (Multiplication test) People think visually Impressive. Lets use it!

Find the Red Square:

Which state has highest Income? Relationship between Income and Education? Outliers?

College Degree % Per Capita Income

Scenarios = Data + Tasks Data categories: Spatial (1,2,3D) Multi-dimensional Tree Network Text, documents

Visualization can do this! User Tasks Easy stuff: (1 or few items) Min, max, average, % Exact queries, known item search Hard stuff: Patterns, trends, distributions, changes over time, outliers, exceptions, relationships, correlations, multi-way, combined min/max, tradeoffs, clusters, groups, comparisons, context, anomalies, data errors, Paths, … Excel can do this Visualization can do this!

DataMaps demo

Spotfire Mapping data to graphics (x, y, size, color, shape…) Multiple views: brushing and linking Dynamic Queries Details window Cars data

TableLens (Eureka by Inxight) Visual encoding of cell values Details expand within context (fisheye) Sorting Cars data

Focus+Context Hyperbolic Tree (star tree) Radial; shrink with distance to center Drag to navigate Scalability? Xerox PARC, Inxight http://startree.inxight.com/

Treemaps on the Web Map of the Market: http://www.smartmoney.com/marketmap/ People Map: http://www.truepeers.com/ Coffee Map: http://www.peets.com/tast/11/coffee_selector.asp

“Squarified” TreeMap http://www.research.microsoft.com/~masmith/all_map.jpg

SequoiaView http://www.win.tue.nl/sequoiaview/ HW #3

Context is Important!

Information Visualization Mantra Overview first, zoom and filter, then details on demand

What is Information Visualization? The use of computer-supported, interactive, visual representations of abstract data to amplify cognition

My definition: Show me the data!

Keys points Power of visual system scenario = data + tasks Mapping data to graphics & visual properties Interaction for what doesn’t fit in visual rep. Examples: multi-dimensional, tree Mantra: Overview first Choice of representation matters

What’s the Big Deal?

Presentation is everything!