Cognitive Walkthrough

1. Cognitive Walkthrough More evaluation without users

2. Project part 4 • Please read the comments on your evaluation plans • Find participants • Friends, neighbors, co-workers • Perform the evaluations • Clearly inform your users what you are doing and why. • If you are audio or video recording, I prefer you use a consent form. • Pilot at least once – know how long its going to take.

3. Part 4 write up • State exactly what you did (task list, how many, questionnaires etc.) • Summarize data collected • Summarize usability conclusions based on your data • Discuss implications for the prototype based on those conclusions

4. 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

5. Cognitive Walkthrough • Qualitative • Predictive • With experts • to examine learnability and novice behavior

6. 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

7. 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

8. 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

9. 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

10. CW: Questions • Will users be trying to produce whatever effect action has? • Will users be able to notice that the correct action is available? (is it visible) • Once found, will they know it’s the right one for desired effect? (is it correct) • Will users understand feedback after action?

11. 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

12. 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

13. 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

14. 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

15. CW: Questions • Will users be trying to produce whatever effect action has? • Will users be able to notice that the correct action is available? (is it visible) • Once found, will they know it’s the right one for desired effect? (is it correct) • Will users understand feedback after action?

16. Let’s practice: PAL

17. User characteristics • Technology savy users • Familiar with computers • Comfortable with basic cell phone operations • Familiar with many features of cell phone, but not expert

18. Task:Party helper • Heather goes to a reception with some conference attendees. Heather doesn’t know many of them but wants to make a good impression since she’ll be looking for a job in a few months, so she wants to use PAL to remind her of names of folks she meets during the evening.

19. Action list • Assume PAL is running… • When introduced to someone new, press “earmark” button and repeat the name. • Assume no intervening introductions… • When there is a break, press and hold the back navigation button until bar reaches earmark. • Listen to name being repeated

20. 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 CW Summary

21. Your turn • Internet radio player • What are our tasks? • What are the actions?

22. CW: Questions • Will users be trying to produce whatever effect action has? • Will users be able to notice that the correct action is available? (is it visible) • Once found, will they know it’s the right one for desired effect? (is it correct) • Will users understand feedback after action?

23. Homework: last one • Cognitive Walkthrough of each other’s prototypes • Gather materials for your prototype: • User characteristics • tasks (1 or 2) and action lists • Storyboard or running prototype • Perform CW for another group