User Interface Evaluation

1. User Interface Evaluation Usability Inspection Methods http://jthom.best.vwh.net/usability/ http://www.cs.umd.edu/~zzj/UsabilityHome.html

2. Usability Inspection Methods • Usability experts “inspect” your interfaces during formative evaluation. • Widely used in practice. • Often abused by developers that consider themselves to be usability experts.

3. Usability Inspection Methods • Heuristic Evaluation • Cognitive Walkthroughs • Pluralistic Walkthroughs • Feature, Consistency & Standards Inspection

4. Heuristic Evaluation • Applicable Stages: • Design, Code, Test & Deployment • Personnel • Usability Experts, approximately 4. • Developers, 0. • Users, 0.

5. Heuristic Evaluation • Usability Issues Covered • Effectiveness: Yes • Efficiency: Yes • Satisfaction: No • Quantitative Data is not collected. • Can be conducted remotely. • Can be used on any system.

6. Heuristic Evaluation • What is it? • Several evaluators independently evaluate the interface & come up with potential usability problems. • It is important that there be several of these evaluators and that the evaluations be done independently. • Nielsen's experience indicates that around 5 evaluators usually results in about 75% of the overall usability problems being discovered.

7. Heuristic Evaluation • How can I do it? • Obtain the service of 4, 5 or 6 usability experts. • Each expert will perform an independent evaluation. • Give experts a heuristics inspection guide. • Collect the individual evaluations. • Bring the experts together and do a group heuristic evaluation. (Optional) • http://www.cs.umd.edu/~zzj/Heuristi.htm

8. Cognitive Walkthroughs • Applicable Stages: • Design, Code, Test & Deployment • Personnel • Usability Experts, approximately 1 - 4. • Developers, 0 - 2. • Users, 0.

9. Cognitive Walkthroughs • Usability Issues Covered • Effectiveness: Yes • Efficiency: No • Satisfaction: No • Quantitative Data is not collected. • Can NOT be conducted remotely. • Can be used on any system, but works best on systems that you can walk up and use systems that don’t require explicit learning.

10. Cognitive Walkthroughs • What is it? • Cognitive walkthroughs involve one or a group of evaluators inspecting a user interface by going through a set of tasks and evaluate its understandability and ease of learning. • The input to the walkthrough also include the user profile, especially the users' knowledge of the task domain and of the interface, and the task cases. • Based upon exploratory learning methods. • Exploration of the user interface.

11. Cognitive Walkthroughs • What is it? • The evaluators may include • Human factors engineers • Software developers • People from marketing • Documentation, etc. • Best used in the design stage of development.

12. Cognitive Walkthroughs • How can I do it? • Select the participants, who will be involved? • Select the tasks, what task will be examined? • Select the interfaces, which interface(s) will be evaluated?

13. Cognitive Walkthroughs • How can I do it? • During the walkthrough: • Illustrate the task and then ask a user to perform a task. • Accept input from all participants: do not interrupt demo. • After the walkthrough: • Make interface changes. • Plan the next evaluation. • http://www.cs.umd.edu/~zzj/CognWalk.htm

14. Pluralistic Walkthroughs • Applicable Stages: • Design • Personnel • Usability Experts, approximately 1. • Developers, 1. • Users, 2.

15. Pluralistic Walkthroughs • Usability Issues Covered • Effectiveness: Yes • Efficiency: No • Satisfaction: Yes • Quantitative Data is not collected. • Can NOT be conducted remotely. • Can be used on any system, but works best on systems that you can walk up and use systems that don’t require explicit learning.

16. Pluralistic Walkthroughs • What is it? • During the design stage, a group of people: • Users • Developers • Usability Experts • Meet to perform a walkthrough.

17. Pluralistic Walkthroughs • How can I do it? • The group meets and 1 person acts as coordinator. • A task is presented to the group. • Paper prototypes, screen shots, etc. are presented. • Each participants write down comments on each interface. • After the demo, a discussion will follow. • http://www.cs.umd.edu/~zzj/PlurWalk.htm

18. Feature, Consistency & Standards Inspection • Applicable Stages: • Code, Testing and Deployment • Personnel • Usability Experts, approximately 1. • Developers, 0. • Users, 0.

19. Feature, Consistency & Standards Inspection • Usability Issues Covered • Effectiveness: Yes • Efficiency: No • Satisfaction: No • Quantitative Data is not collected. • Can be conducted remotely. • Works best on in house systems that have standards.

20. Feature, Consistency & Standards Inspection • What is it? • Feature, Consistency & Standards are inspected by an expert.

21. Feature, Consistency & Standards Inspection • How can I do it? • Feature Inspection • The expert is given use cases/scenarios and asked to inspect the system. • Consistency Inspection • The expert is asked to inspect consistency within your application. • Standards Inspection • The expert is asked to inspect standards. • Standards can be in house, government, etc.

22. Heuristic Evaluation A Closer Look At How To Evaluate Interfaces

23. A Closer Look At Heuristic Evaluation • Evaluation is easier than design. • The principles that drive design, drive evaluation as well.

24. 5 Human Factors Principles • Language • Layout • Color • Tone & Etiquette • Special Considerations such as standards, disabilities, etc.

25. Evaluating Language • What is the language? • English, Chinese, Hindi, etc. • Do the text messages convey a message? • If so, what is the message? • Is the text long, short, organized, etc.

26. Evaluating Layout • Symmetry • Is the interface symmetrical? • Left-Right, Top-Bottom, Center • Attention & Focus • Where does your attention & focus go?

27. Evaluating Color • Contrast • Are the color contrasts good? • What meanings do the colors convey? • Pink … it’s a girl. • Blue … it’s a boy.

28. Evaluating Tone & Etiquette • Is the language offensive? • Are the messages polite? • Will the content offend anyone?

29. Evaluating Special Considerations • Features, Consistency & Standards. • Does it work the way it is suppose to work? • Is it consistent? • Does it follow the standards? • Disabilities

30. Affordances, Mappings & Constraints • Use Affordances, Mappings & Constraints to evaluate interfaces and products. • Use Affordances, Mappings & Constraints to design interfaces and products.

31. Affordances • Affordances refers to the perceived and actual properties of the “thing” that determine just how the “thing” could be used. • The appearance of the “thing” tells you how to use it.

32. Mapping • The relationship between two things, in most cases the mapping from digital world to real world. • Metaphors and analogies.

33. Constraints • Limitations on the product. • Physical Constraints • Those that limit our physical use of the product. • Semantic Constraints • Relies upon semantic meaning & knowledge. • Example: automobile’s windshield faces forward, therefore, you drive the car facing the windshield.

34. Constraints • Logical Constraints • There are the obvious, yet logical constraints. • You can’t see items outside of your screen’s view port. • Cultural Constraints • Things that are specific to the user’s culture. • Example: Americans drive on the opposite side of the road versus Europeans and West Indians.

35. Evaluating Interfaces • Look for • Affordances, Mappings & Constraints • Language • Layout • Color • Tone & Etiquette • Special Considerations such as standards, disabilities, etc.

36. 5 Human Factors Principles • Language • Layout • Color • Tone & Etiquette • Special Considerations such as standards, disabilities, etc.