1. Chapter 6 Thinking about requirements and describing them

2. Usability Requirements
The desired qualitative or quantitative usability goals for a system
Qualitative – desired goals for usability
Quantitative – usability metrics
UIDE Chapter 6

3. Early Views of Usability
Learnability – time and effort required to reach a specified level of use performance
Throughput – tasks accomplished by experienced users, speed, and errors
Flexibility – extent to which system can accommodate changes
Attitude – positive attitude of users
UIDE Chapter 6

4. Usability The Modern-Day View of Usability 5 Es Effective Efficient
Engaging
Error tolerant
Easy to learn
UIDE Chapter 6

5. Constraints and Trade-offs in Relation to Requirements Gathering
Costs/Budgets/Timescales
Technical Constraints
Trade-Offs
UIDE Chapter 6

6. Problems with Requirements Gathering Requirements Specification
User characteristics
Tasks and task characteristics
Environmental factors
Usability
Constraints and trade-offs
UIDE Chapter 6

7. Prototyping Purposes of Prototyping: Why Bother Trying Out Your Ideas?
Check feasibility of ideas with users
Check usefulness of the application
Allow users to contribute
Allow users to test ideas
Validate requirements
Negotiate requirements
UIDE Chapter 6

8. Prototyping Low-Fidelity Prototypes Sketching Screen Mockups
Storyboards
UIDE Chapter 6

9. High-Fidelity Prototypes: Using Software Tools to Try Out Your Ideas
Cautions about Prototyping
UIDE Chapter 6