1. Discount Evaluation Evaluating with experts

2. Agenda Project was due today – You will demo your prototype next class Heuristic Evaluation Cognitive Walkthrough

3. Discount Evaluation Techniques Basis: – Observing users can be time-consuming and expensive – Try to predict usability rather than observing it directly – Conserve resources (quick & low cost)

4. Approach - inspections Expert reviewers used – HCI experts interact with system and try to find potential problems and give prescriptive feedback – Best if Haven’t used earlier prototype Familiar with domain or task Understand user perspectives

5. Discount Evaluation Methods 1. Scenarios 2. Heuristic Evaluation 3. Cognitive Walkthrough

6. Heuristic Evaluation Developed by Jakob Nielsen Several expert usability evaluators assess system based on simple and general heuristics (principles or rules of thumb) (Web site: www.useit.com )

7. Heuristic Evaluation Mainly qualitative use with experts predictive

8. Procedure 1. Gather inputs 2. Evaluate system 3. Debriefing and collection 4. Severity rating

9. 1: Gather Inputs Who are evaluators? – Need to learn about domain, its practices Get the prototype to be studied – May vary from mock-ups and storyboards to a working system

10. How many experts? Nielsen found that about 5 evaluations found 75% of the problems Above that you get more, but at decreasing efficiency

11. 2: Evaluate System Reviewers evaluate system based on high- level heuristics. Where to get heuristics? – http://www.useit.com/papers/heuristic/ http://www.useit.com/papers/heuristic/ – http://www.asktog.com/basics/firstPrinciples.html

12. Heuristics use simple and natural dialog speak user’s language minimize memory load be consistent provide feedback provide clearly marked exits provide shortcuts provide good error messages prevent errors

13. Neilsen’s Heuristics visibility of system status aesthetic and minimalist design user control and freedom consistency and standards error prevention recognition rather than recall flexibility and efficiency of use recognition, diagnosis and recovery from errors help and documentation match between system and real world

14. Groupware heuristics Provide the means for intentional and appropriate verbal communication Provide the means for intentional and appropriate gestural communication Provide consequential communication of an individual’s embodiment Provide consequential communication of shared artifacts (i.e. artifact feedthrough) Provide Protection Manage the transitions between tightly and loosely-coupled collaboration Support people with the coordination of their actions Facilitate finding collaborators and establishing contact Baker, Greenberg, and Gutwin, CSCW 2002

15. Ambient heuristics Useful and relevant information “Peripherality” of display Match between design of ambient display and environments Sufficient information design Consistent and intuitive mapping Easy transition to more in-depth information Visibility of state Aesthetic and Pleasing Design Mankoff, et al, CHI 2003

16. Process Perform two or more passes through system inspecting – Flow from screen to screen – Each screen Evaluate against heuristics Find “problems” – Subjective (if you think it is, it is) – Don’t dwell on whether it is or isn’t

17. 3: Debriefing Organize all problems found by different reviewers – At this point, decide what are and aren’t problems – Group, structure – Document and record them

18. 4: Severity Rating Based on – frequency – impact – persistence – market impact Rating scale – 0: not a problem – 1: cosmetic issue, only fixed if extra time – 2: minor usability problem, low priority – 3: major usability problem, high priority – 4: usability catastrophe, must be fixed

19. Advantages Few ethical issues to consider Inexpensive, quick Getting someone practiced in method and knowledgeable of domain is valuable

20. Challenges Very subjective assessment of problems – Depends of expertise of reviewers Why are these the right heuristics? – Others have been suggested How to determine what is a true usability problem – Some recent papers suggest that many identified “problems” really aren’t

21. Your turn: Library – main page, finding a book Use Nielsen’s heuristics (p 686) List all problems Come up to the board and put up at least one new one We’ll rate as a group

22. Neilsen’s Heuristics visibility of system status aesthetic and minimalist design user control and freedom consistency and standards error prevention recognition rather than recall flexibility and efficiency of use recognition, diagnosis and recovery from errors help and documentation match between system and real world

23. Heuristic Evaluation: review Design team provides prototype and chooses a set of heuristics Experts systematically step through entire prototype and write down all problems Design team creates master list, assigns severity rating Design team decides how to modify design

24. Cognitive Walkthrough

25. 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

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

27. 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

28. 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

29. 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

30. 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

31. CW: Questions 1. Will users be trying to produce whatever effect action has? 2. Will users be able to notice that the correct action is available? (is it visible) 3. Once found, will they know it’s the right one for desired effect? (is it correct) 4. Will users understand feedback after action?

32. 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

33. 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

34. 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

35. 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

36. Let’s practice: My Internet Radio

37. User characteristics Technology savy users Familiar with computers Understand Internet radio concept Just joined and downloaded this radio

38. Task: find a new station to presets Click genre Scroll list and choose genre Assuming station is on first page, add station to presets -- right-click on station, choose add to presets from popup menu. Click OK on Presets

39. Task: Click – Pick a genre 1. Will users be trying to produce whatever effect action has? 2. Will users be able to notice that the correct action is available? 3. Once found, will they know it’s the right one for desired effect? 4. Will users understand feedback after action?

40. Action: Add to Preset 1. Will users be trying to produce whatever effect action has? 2. Will users be able to notice that the correct action is available? 3. Once found, will they know it’s the right one for desired effect? 4. Will users understand feedback after action?

41. Action: Click OK 1. Will users be trying to produce whatever effect action has? 2. Will users be able to notice that the correct action is available? 3. Once found, will they know it’s the right one for desired effect? 4. Will users understand feedback after action?

42. CW Summary 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

43. Your turn Library finding book What are our tasks? What are the actions?

44. CW: Questions 1. Will users be trying to produce whatever effect action has? 2. Will users be able to notice that the correct action is available? (is it visible) 3. Once found, will they know it’s the right one for desired effect? (is it correct) 4. Will users understand feedback after action?

45. CW: review Design team creates prototype, user characteristics Design team chooses tasks, lists out every action and response Experts answer 4 questions for every action/response Design team gathers responses and feedback Design determines how to modify the design

46. Next time Heuristic evaluation of your own prototypes Bring to class – Your prototype – Any other sketches, storyboards, etc. that you have to convey your design – Set of heuristics you want them to use, print them out

47. Process Pairs of teams will evaluate each other One team demo, then the other team Then write down everything you find and give list to the team Project team compiles all the problems, assign severity rating, include in your Part 3 writeup TA and I will interrupt each team to demo their prototype

48. Heuristic Eval team pairs Mighty Morphin and UCook College Registration and Laguna Bleach One Password and Food Networking Team No Name and Best for Last

49. 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

50. Homework Best for Last and Mighty Morphin UCook and College Registration Laguna Bleach and One Password Food Networking and No Name To turn in on your group page: – List of tasks and actions for your prototype – Date and people who evaluated your prototype Due: April 15 after class