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Cognitive Walkthrough More evaluating with experts
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Cognitive Walkthrough More evaluating with experts.

Jan 06, 2018

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Sophie Jacobs

Cognitive Walkthrough Assess learnability and usability through simulation of way users explore and become familiar with interactive system A usability “thought experiment” Like code walkthrough (s/w engineering) From Polson, Lewis, et al at UC Boulder
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Page 1: Cognitive Walkthrough More evaluating with experts.

Cognitive Walkthrough

More evaluating with experts

Page 2: Cognitive Walkthrough More evaluating with experts.

Review

Discount evaluation techniques– Use experts to predict usability problems– Likely to be cheaper and faster with fewer ethical

issues Heuristic evaluation

– Experts identify potential problems in a design or prototype based on set of guiding heuristics

Page 3: Cognitive Walkthrough More evaluating with experts.

Cognitive Walkthrough

Assess learnability and usability through simulation of way users explore and become familiar with interactive system

A usability “thought experiment” Like code walkthrough (s/w engineering) From Polson, Lewis, et al at UC Boulder

Page 4: Cognitive Walkthrough More evaluating with experts.

Cognitive Walkthrough

Qualitative Predictive With experts

to examine learnability and novice behavior

Page 5: Cognitive Walkthrough More evaluating with experts.

CW: Process

Construct carefully designed tasks from system spec or screen mock-up

Walk through (cognitive & operational) activities required to go from one screen to another

Review actions needed for task, attempt to predict how users would behave and what problems they’ll encounter

Page 6: Cognitive Walkthrough More evaluating with experts.

CW: Assumptions

User has rough plan User explores system, looking for actions to

contribute to performance of action User selects action seems best for desired

goal User interprets response and assesses

whether progress has been made toward completing task

Page 7: Cognitive Walkthrough More evaluating with experts.

CW: Requirements

Description of users and their backgrounds Description of task user is to perform Complete list of the actions required to

complete task Prototype or description of system

Page 8: Cognitive Walkthrough More evaluating with experts.

CW: Methodology

Step through action sequence– Action 1– Response A, B, ..– Action 2– Response A– ...

For each one, ask four questions and try to construct a believability story

Page 9: Cognitive Walkthrough More evaluating with experts.

CW: Questions

1. Will users be trying to produce whatever effect action has?

2. Will users be able to notice that the correct action is available? (is it visible)

3. Once found, will they know it’s the right one for desired effect? (is it correct)

4. Will users understand feedback after action?

Page 10: Cognitive Walkthrough More evaluating with experts.

CW: Answering the Questions

1. Will user be trying to produce effect?– Typical supporting evidence

It is part of their original task They have experience using the system The system tells them to do it

– No evidence? Construct a failure scenario Explain, back up opinion

Page 11: Cognitive Walkthrough More evaluating with experts.

CW: Next Question

2.Will user notice action is available?– Typical supporting evidence

Experience Visible device, such as a button Perceivable representation of an action such as a menu

item

Page 12: Cognitive Walkthrough More evaluating with experts.

CW: Next Question

3.Will user know it’s the right one for the effect?– Typical supporting evidence

Experience Interface provides a visual item (such as prompt) to

connect action to result effect All other actions look wrong

Page 13: Cognitive Walkthrough More evaluating with experts.

CW: Next Question

4.Will user understand the feedback?– Typical supporting evidence

Experience Recognize a connection between a system response

and what user was trying to do

Page 14: Cognitive Walkthrough More evaluating with experts.

Let’s practice: My Internet Radio

Page 15: Cognitive Walkthrough More evaluating with experts.

User characteristics

Technology savy users Familiar with computers Understand Internet radio concept Just joined and downloaded this radio

Page 16: Cognitive Walkthrough More evaluating with experts.

Task: add a station to presets

Click genre Scroll list and choose genre Assuming station is on first page, add station

to presets -- right-click on station, choose add to presets from popup menu.

Click OK on Presets

Page 17: Cognitive Walkthrough More evaluating with experts.

Task:Click – Pick a genre

1. Will users be trying to produce whatever effect action has?

2. Will users be able to notice that the correct action is available?

3. Once found, will they know it’s the right one for desired effect?

4. Will users understand feedback after action?

Page 18: Cognitive Walkthrough More evaluating with experts.

Scroll list and choose genre

1. Will users be trying to produce whatever effect action has?

2. Will users be able to notice that the correct action is available?

3. Once found, will they know it’s the right one for desired effect?

4. Will users understand feedback after action?

Page 19: Cognitive Walkthrough More evaluating with experts.

Action: Right click on station and choose “Add to Presets”

1. Will users be trying to produce whatever effect action has?

2. Will users be able to notice that the correct action is available?

3. Once found, will they know it’s the right one for desired effect?

4. Will users understand feedback after action?

Page 20: Cognitive Walkthrough More evaluating with experts.

Action: Click OK

1. Will users be trying to produce whatever effect action has?

2. Will users be able to notice that the correct action is available?

3. Once found, will they know it’s the right one for desired effect?

4. Will users understand feedback after action?

Page 21: Cognitive Walkthrough More evaluating with experts.

Problems

Did I pick the right task? Or list out the right sequence of actions?

Page 22: Cognitive Walkthrough More evaluating with experts.

CW Summary

Advantages Explores important

characteristic of learnability

Novice perspective Detailed, careful

examination Working prototype not

necessary

Disadvantages Can be time consuming May find problems that

aren’t really problems Narrow focus, may not

evaluate entire interface

Page 23: Cognitive Walkthrough More evaluating with experts.

Your turn

Library - finding book

What are our tasks?

What are the actions?

Page 24: Cognitive Walkthrough More evaluating with experts.

CW: Questions

1. Will users be trying to produce whatever effect action has?

2. Will users be able to notice that the correct action is available? (is it visible)

3. Once found, will they know it’s the right one for desired effect? (is it correct)

4. Will users understand feedback after action?

Page 25: Cognitive Walkthrough More evaluating with experts.

CW: responsibilities

Design team creates prototype, user characteristics Design team chooses tasks, lists out every action

and response Experts answer 4 questions for every

action/response Design team gathers responses and feedback Design team determines how to modify the design