Lecture 12: Cognitive Walkthroughs

Question 1

What are the THREE models within interaction modelling?

Answer 1

1. User Model
2. Designer Model
3. System Image

Question 2

What is the User Model?

Answer 2

The user model is the user’s mental image of how their tasks should be accomplished through interacting with the system.

Question 3

What is the Designer Model?

Answer 3

The designer model is the designer’s mental image of how the system should function to implement the use cases identified.

Question 4

What is the System Image?

Answer 4

The system image is the mental model users derive from interacting with the physical system - this image is the only way designers communicate with the users.

Question 5

What is the interaction model?

Answer 5

User Goals –> intention –> planning –> execution –> system –> perception –> interpretation –> evaluation –>

Question 6

What is the Gulf of Execution?

Answer 6

The gulf of execution is the distance between the user’s goals and the means of achieving them through the system.
Within the interaction model the gulf of execution involves intention, planning and execution.

Question 7

What is the Gulf of Evaluation?

Answer 7

The gulf of evaluation is the amount of effort required to determine the system state; did it do what the user wanted in the way that was expected?
Within the interaction model the gulf of evaluation involves perception, interpretation and evaluation.

Question 8

What is a cognitive walkthrough?

Answer 8

A cognitive walkthrough is an evaluation method by inspection. It is based on task-oriented inspection with a focus on learnability of the interface. The cognitive walkthrough has two steps:

1. Task Analysis
2. Evaluate Task

Question 9

What is the first step of the cognitive walkthrough and what does it involve?

Answer 9

Task Analysis

This stage involves identifying the user population, identify tasks to be evaluated and analyse & document tasks.

Question 10

What the second step of the cognitive walkthrough and what does it involve?

Answer 10

Evaluate Task
For each state / action identified answer four questions, document the answer to the questions and report whether it succeeds or fails and document the usability problems found on a standard evaluation card.

Question 11

In second step of the cognitive walkthrough what are the four questions which must be answered?

Answer 11

1. Will the user know what sub-goal they want to achieve?
2. Will the user find the action in the interface?
3. Will the user recognise the action which accomplishes the sub-goal?
4. Will the user understand the feedback of the action?

Question 12

What are the FOUR advantages of the cognitive walkthrough?

Answer 12

1. Finds tasks-oriented problems
2. Helps define users’ goals and assumptions
3. Usable early in development process
4. Can be used as part of Heuristic Evaluation (HE).

Question 13

What are the THREE disadvantages of the cognitive walkthrough?

Answer 13

1. Some training is required
2. Needs task definition methodology
3. Applies only to ease of learning problems