SBD:Information Design - Virginia Techcs3724/fall2005-bowman/... · 2005. 9. 12. · R efin dorsp R...

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SBD:Information Design

CS 3724

Thanks to Chris North and Scott M cCrickard for their original slides.

Problem scenarios

summativeevaluation

Information scenarios

claims aboutcurrentpractice

analysis ofstakeholders,field studies

Usability specifications

Activityscenarios

Interaction scenarios

iterativeanalysis ofusability claims andre-design

metaphors,informationtechnology,HCI theory,guidelines

formativeevaluation

DESIGN

ANALYZE

PROTOTYPE & EVALUATE

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Information Design Goal: identify methods for representing and

arranging the objects and actions possible ina system in a way that facilitates perceptionand understanding

Define and arrange the visual (or othermodality) elements of a user interface “Big picture”, overall info model Detailed screen layout

Activity design scenarios:transform current activities to

use new design ideas

Information design scenarios:Elaborate to include visual

presentation details

Problem andactivity designclaims: look for

representations thataddress negatives,but keep positives

+/-

Informationdesign space:

brainstormrepresentations in

metaphors andtechnology

HCIknowledge

aboutinformation

designClaims analysis: features ofthe information design with key

implications for use+/-

SBD andInformationDesign

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Execution

Action plan

Systemgoal

Last month’sbudget... ?

Interpretation

PerceptionMakingsense GULF OF

EVALUATION

GULF OFEXECUTION

Stages of Action in HCIfocus ofinformationdesign

focus ofinteractiondesign

Last month’sbudget... ?

Making Sense of an Information Display

color, shading, linescharacters, squares,spatial organization

Excel worksheet, a cellis selected, formula isdisplayed at top

Income worksheet,Total tax income is beingcalculated, the wrong multiplier is being used

Making Sense

Interpretation

Perception

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Analogy to verbalcommunication1. Hear

Sound waves Syllables

2. Parse Syntax Language = vocabulary + grammar

3. Understand Semantics, meaning

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Human Vision Highest bandwidth sense (100 MB/sec) Dominant sense (50% of brain involved in

processing visual information) Parallel processing Pre-attentive Pattern recognition Extends memory and cognitive capacity People think visually Visual attention (fovea vs. periphery,

saccades)

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Perception Visually encode information Vision:

lines, shapes, colors “extracted” grouped as rows, columns, grids, … very fast, generally with no conscious thought

Design goal: make perceptual process rapid and accurate

Which state has highest income? Relationship between income and education? Outliers?

Per Capita Income

Colle

ge D

egre

e %

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Gestalt Principles ofPerception

Proximity Similarity

Closure Area

Symmetry Continuity

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Gestalt in User InterfaceDesign

Try the “squint test”...What principles are in action?

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Minimal significant difference To organize information, elegant

designs exploit: position, thematic repetition, low-key color

schemes, and white space, Instead of:

lines, boxes, and labels

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Interpretation Results of perception are recognized Visual language

Design goal: make the interpretationprocess rapid and accurate

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Leveraging Familiarity Familiar “vocabulary”:

Widgets Text Labels Speak the user’s language

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Images: Realism andRefinement Abstract:

Road signs Refined for speed

Realistic images Accurate and memorable but are more complex, take longer to process

Remove unnecessarydetail

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Leveraging Affordances An affordance gives clues about how to

use an object door knob, steering wheel, pen scrollbar, title bar, window “handles” pointer feedback

Visible vs. popup

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Affordances

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Making Sense of Information Connecting to user tasks:

Do I understand what the system is telling me? Were my actions successful? Have I made progress?

Build the “big picture”

Design goal: help the user makeconnections between UI information and taskgoals Execution/evaluation cycle

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Consistency Internal consistency (within a system)

On the same screen: button shape, labels, fonts, From screen to screen: UI controls, layout Vocabulary consistency: e.g. “previous/next”

instead of “previous/down” External consistency (between systems, or

with real world) Why?

More rapid/accurate pattern recognition More confident interaction behavior Transfer of learning

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Information Integration

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VisualMetaphors A physical

calculator as avisual metaphor

What is good or badabout this design?

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Information Models An “information space” or structure that

users navigate Common models:

spatial: timelines (1D), maps (2D), VR (3D) tabular: lists, tables, databases hierarchy: menu systems, folders, index pages directed graph: hypertext, web

Which network is easier to understand?

Menu Guidelines

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Breadth vs. Depth Broad-shallow vs. narrow-deep Depth = logbranchingFactor numPages Usability: max depth ≈ 3-4

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Where to put knowledge In the head

memory (long-term or working?) what level of precision?

In the world “external storage” for a user problem of display clutter

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Short-term memory load Remember the “magical number 7+/- 2” Chunking of information

My goal:find ratingsconcerningSony Vaiolaptops