WEEK 10 Usability Engineering Evaluation Concepts

These flashcards cover key terms and definitions related to usability evaluation methods and concepts discussed in the lecture.

Usability Evaluation

A process through which information about the usability of a system is gathered in order to improve it or to assess a completed interface.

Cognitive Walkthrough

A method to evaluate how well a system supports users learning a task by having an expert walk through the design to identify potential problems.

Discount Usability Testing

An approach to usability evaluation that emphasizes quick and inexpensive methods to identify usability issues.

Formative Evaluation

Evaluation conducted during the development process to improve and guide decisions about the design.

Summative Evaluation

Evaluation that takes place at the end of the design process to assess whether the system meets intended goals and requirements.

Visibility of System Status

A principle stating that the system should keep users informed about what is going on through appropriate feedback.

Match Between System and the Real World

A principle that suggests the design should use concepts familiar to users instead of internal jargon.

User Control and Freedom

A principle indicating that users should be able to easily undo and redo actions.

Error Prevention

A design principle focused on eliminating error-prone conditions or checking for them before the user commits to an action.

Consistency & standards

A usability principle stating that similar operations should be presented in similar ways, and standard conventions should be followed to help users understand the interface.

Recognition over Recall

shows options instead of relying on memory

Flexibility & efficiency of use

Shortcuts for user experts

Aesthetic & minimalist design

Avoids unnecessary detail

Helps recognise, diagnose and recover from errors

Clear error messages are displayed to inform users

Help and Documentation

User assistance

Step 1 for Cognitive walkthrough

Select a task to be preformed and write down all the steps in the task

Step 2 for Cognitive Walkthrough

Then for each actions in the tasks you ask questions

Step 3 for Cognitive walkthrough

You ask:
Will they understand it & know what to do next
Will they understand feedback

What impact will the interaction have on the user

Cognitive processes required
Learning problems

Pros of Cognitive Walkthrough

Identifies usability issues early, allows analysis of user decision-making, and helps in understanding user expectations.

Cons of Cognitive Walkthrough

May overlook real user behavior, requires familiarity with tasks, can be time-consuming, and may not capture all usability issues.

Advantages of Usability Heuristic

• Quick and low-cost (no real users needed)

• Detects common design issues early

• Small team can conduct it (3–5 evaluators effective)

• Based on a structured framework (e.g., Nielsen's 10 rules)

Disadvantages of Usability Heuristic

• Depends heavily on evaluator expertise

• May miss user-specific or context-specific issues

• Not all problems found are equally important

• Can lead to false positives (problems that aren’t real)