Defining Your Domain: User / Task / Environmental Analysis

1. Defining Your Domain: User / Task / Environmental Analysis HCC 729, 2/6/14

2. In-class Homework Critiques Choose domain and partner for project…

3. Anatomy of a successful project PGF Website Redesign Analysis of Current Site and Proposed Prototypes for the Potters’ Guild of Frederick Week 2

4. Week 3

5. Week 3

6. Week 4

7. Week 4

8. Week 5

9. Week 6

10. Week 7

11. Wordpress Questions / Help?

12. Discussion Inspirations or UI news? Readings

13. User / Task / Environmental Analysis

14. User Analysis Why do you need to know your user?

15. Why perform user analysis? • Design / build systems that meet user needs • Attract new / keep current customers (or users) • Reduce development and maintenance costs • Discover new human behaviors / trends • Discover new user subgroups • …

16. A brief list of user characteristics • Age • Gender • Culture • Language • Ability • Education (reading level) • Experience • …. Other examples?

17. User characteristics: physical differences • Age (use larger fonts for older people) • Sex (consider your target group: e.g., more women than men buy lipstick) • Vision limitations, such as color blindness • Other physical limitations that might restrict movement (See Chapter 12) • Small children don’t have good fine-muscle control: see big buttons on next slide

18. User characteristics: tool preferences • Do your users know drop-down menus? • Do they prefer mouse or keyboard? (Some advanced users hate the mouse: it slows them down.) • Do they know frames? Popup windows? Search? • You won’t believe how different new users are, compared to you, until you watch them

19. User characteristics: knowledge of job • Is your site used daily on the job, or it is used at home for recreation or a hobby? • Is there a specialized vocabulary? • If in an office, how does work on your site fit in with other activities? Could your user answer that question? • Does your user do the same job all day? Bored? • If for personal use, what is the purpose? • To inform • To entertain • To sell

20. User characteristics: application familiarity • Novice Faces a frightening unknown; timid, nervous, in no mood to explore your goodies • Advanced Beginner Less fear: knows basics; still impatient at having to learn how to do tasks. • Competent Performer Can diagnose simple problems and can perform a complex series of tasks • Expert Small group. Can diagnose complex problems. Has a mental model of the application. Not typical users.

21. User characteristics: primary and secondary users • Primary user: the person who actively uses the site: Airline reservation clerk Help desk staff • Secondary user: the person being served by a primary user: Airline passenger Customer who called the support line

22. Task Analysis Task analysis describes what your users are doing.

23. Task Analysis Overview Develop an understanding of your user’s life • What tasks they perform • Why they perform these tasks • How they perform them

24. Approach, notations and techniques • Task decomposition • Splitting task into (ordered) subtasks • Knowledge based techniques • List what what the user knows about the task and how it is organized • List all objects and actions involved in the task, and then build taxonomies of them • Entity/object based analysis • Relationships between objects, actions and the people who perform them • Won’t cover this today (Section 15.5 of reading)

25. When making your own TA… • What is the main goal you are trying to support? • What data do you have to indicate this is important to users? • What are the sub goals you want to support? • Which are most important to your stakeholders? • Which does your prototype implement? • List these goals and sub goals, and then try making a TA to describe your system.

26. Two Types of Task Decomposition • Hierarchical Task Analysis (HTA) – descriptions of information requirements for lowest level sub-operations including a dictionary of objects and associated actions • Cognitive Task Analysis (CTA) – Includes cognitive characteristics of task space (e.g. cognitive load, response time, cognitive processing, display interpretation). • Will not be focusing on CTA in this class

27. Hierarchical Task Analysis

28. Hierarchical Task Analysis • Decompose tasks to express a structure • Describe an activity in terms of: • tasks, subtasks, and plans • order things are completed • the conditions subtasks are performed • Useful for decomposing complex tasks • Has a narrow view of the task

29. Types of Hierarchical Task Analysis Textual HTA Diagrammatic HTA

30. HTA Terms • Task / Sub-task • Objects – things used in the task • Actions - performed • Goal / Sub-goal • Plan – steps taken to reach goal

31. Hierarchical Task Analysis Example Let’s describe how you make tea in a pot (not a microwave)

32. What are the steps to make tea? Domain specific knowledge… Kettle Pot

33. Top-Level Tea Tasks Task 0. Make a cup of tea • Boil water in kettle • Empty old water in pot (if any) • Make pot of tea • Wait 4-5 minutes • Pour tea

34. Tea Plan Task 0. Make a cup of tea • Boil water in kettle • Empty old water in pot (if any) • Make pot of tea • Wait 4-5 minutes • Pour tea • Plan 0 for Task 0. • Do 1 • While A, if pot is full, • do 2 • Then do 3 and 4 • After 5 min do 5

35. Tea Plan Task 0. Make a cup of tea • Boil water in kettle • Empty old water in pot (if any) • Make pot of tea • Wait 4-5 minutes • Pour tea Put tea leaves in pot Pour in hot water But what does this entail? • Plan 0 for Task 0. • Do 1 • While A, if pot is full, • do 2 • Then do 3 and 4 • After 5 min do 5

36. Tea Plan Task 0. Make a cup of tea • Boil water in kettle • Empty old water in pot (if any) • Put Leaves in pot • Pour in hot water • Wait 4-5 minutes • Pour tea • Plan 0 for Task 0. • Do 1 • While A, if pot is full, • do 2 • Then do 3 - 5 • After 5 min do 6

38. But is this good enough? • Now that we have our first HTA, we ask “What have we missed or gotten wrong?” • Ask experts to look at our HTA, but do they have expert blindspots? • We can examine subtasks and think about them in context of whole system. • 1.4 says turn off gas, but did we ever turn it on?

41. Types of plans • sequence 1.1 then 1.2 then 1.3 • optionalif the pot is full 2 • waitwhen kettle boils, do 1.4 • cyclesdo 5.1 5.2 while there are still empty cups • paralleldo 1; at the same time … • discretionarydo any of 1.3.1, 1.3.2 or 1.3.3 in any order

43. When do you stop? • How many subtasks should you include? • P X C Rule • Multiply probability that the user will make a mistake in the task by the cost of the mistake. • Stop adding subtasks if this is below a threshold • Only expand important or critical tasks • Stop when you can’t easily describe subtasks • Internal decision making or motor responses • Stop when you have fully described the situation

44. Knowledge-Based Analysis

45. KBA – How to start • List all objects and actions involved in the task • Build taxonomies (groups) of all objects and actions • Work with target user to define / organize groups so you capture their knowledge

46. KBA example

47. How do you create taxonomies? • Card sorting with an expert / target user • Organize things into similar piles on paper. • Name the pile • Split it into 2 piles • Make it more explicit • What if it spans multiple categories?

48. TAKD and TDH • Task analysis for knowledge description (TAKD) uses Task Descriptive Hierarchies(TDH) to handle branching: • XOR — object in exactly one branch • AND — object must be in both • OR — can be in one, many or none

49. TDH example • A plate may be used for preparation or dining

50. Why is this useful?