Quiz 3

Design hints how to use it (handle = pull)

A cue showing how to use it ("Push" sign)

Clear what a control will do (stove dial icons)

How to use it vs. what it does

User can see the system's state

Same experience for all users

Physical, cultural, semantic, logical

Predictability, synthesizability, familiarity, generalizability, consistency

User can see how they got here (undo history)

Show relationships, cut extra details, show constraints

Learn fast with little experience (good)

Right idea, wrong action

Wrong idea, wrong action

Wrong action vs. forgot an action

Wrong decision vs. misread the situation

User gives up because nothing works

Experts forget what novices don't know

Goals, Operators, Methods, Selection rules

Smallest actions

How the user picks a method

Assumes experts; ignores errors

Add up action times to predict task time

GOMS with a goal hierarchy

GOMS in plain language

Studies the user's thinking (memory, attention)

Slow, ignores context, bad for novices

Break tasks into smaller subtasks

Qualitative, empirical, predictive

Consistent vs. accurate

Results apply to others

Improve the design vs. prove the result

Efficiency, accuracy, learnability, memorability, satisfaction

Talk while using vs. feedback after

One treatment each vs. all treatments each

Under 5% chance it's random

Chi-squared

t-test

ANOVA

Success or fail data

False positive

Experts check against design rules

Step through tasks as a novice

Changes with the IV and muddies results

Caused by the IV vs. applies to the real world

Earlier conditions affect later ones

Mix up the order of conditions

Each condition once in each position

One evaluator misses most problems; use 3–5

Cheap and fast, but gives no fixes

Learning by exploring

CE+ theory