DESIGN AND EVALUATION

1. DESIGN AND EVALUATION HCI Class Presentation Group Members: Petra Leimert, Alexander Stevenson, Martin Kyle, Farhan Mohamed, Lisa Tong

2. Overview • Design Principles • Design Goals • Design Process • Design Methodologies • User Centered • Heuristics

3. Design Principles • Know the user • Minimize memorization • Allowing selection of items rather than entry of data • Using names instead of numbers • Optimize operations • Providing rapid execution of common operations • Preserving display consistency • Engineer for errors • Allowing actions to be reversible • Guaranteeing system integrity in the face of hardware or software failure

4. Design High Level Goals • Comber, 1996 • Aesthetics • Navigation • Comprehension • Learnability • Efficiency • Memorability • Error handling • User satisfaction

5. Design Methodologies • Gould, Boies, and Lewis (1991)’s four design principles • Early focus on users • Talk with user • Visit customer locations … • Early-and continual-user testing • Early user manuals • Mock-ups • Field studies … • Iterative design • Software tools • System develoment work organization • Integrated design • Consider all aspects of usability in the initial design • One person or group has responsibility for all aspects of usability

6. Design Methodologies • Rubinstein and Hersh (1984) • Information collection • Goals, Market requirements, technical requirements • Current state of the art, competing products • Industry stansards, government regulation … • System design • External myth, conceptual model, and use model • Methods for error handling and recovery • Implementation • Prototype and System • Evaluation • Formal and informal • Deployment • Delivery, evaluation of the reactions of the user and the marketplace to it

7. Design Methodologies • SIGCHI 1999 Survey • HCI Professionals attending SIGCHI 1999 were surveyed about what design methodologies they thought were most effective. These survey results were published the following year. • e.g. Rosenbaum, Rohn, and Homburg. A Toolkit for Strategic Usability. 2000. CHI Letters.

8. Design Approaches • The most promising approach • Iterate design and evaluation until a satisfactory result is achieved • Process • Evaluation of existing systems, • Evaluation of current work practices and organizational setting, • Evaluations of rapid prototypes and mock-ups, • Evaluations of alpha and beta versions • FEEDBACK INTO DEVELOPMENT CYCLE

9. Requirements specification Architectural design Detailed design Coding and unit testing Integration and testing Evaluation and maintenance Design Process • Activities in the development cycle

10. Requirements and Specifications • Brooks • “I believe the hard part of building software to be the specification, design, and testing of this conceptual construct, not the labor of representing it and testing the fidelity of the representation.” • From “No Silver Bullet”

11. Interaction Design Applied

12. Interaction Design Applied

13. Interaction Design Applied

14. Interaction Design Applied

15. Design Methodologies • Our Focus Today • User Centered Design • Heuristics

16. User Centered Design • Enhanced approach to development: • User profiles • User requirements • Participatory Methods • Usability Testing • Iterative design and evaluation

17. Standards-Guidelines Task analysis Design history Requirements analysis Design tools Usability testing Design Formative evaluation Evaluation Implementation Summative evaluation User Centered Design Process • Adapted from Preece, 1993

18. User Profiles • Understand user at many levels • Social Condition • Education Level • Personal Interests • Computer Literacy • System Role

19. Participatory Methods • Wishlists • Beta Programs • Feature Councils

20. Heuristic Design & Evaluation • Systems are designed by looking at a small set of very general “design guidelines” (called heuristics). • Heuristics often help designers avoid common pitfalls in human computer interaction.

21. Heuristic Guidelines for Dialog Design • “Eight Golden Rules of Dialog Design” Shneiderman (1992) • Strive for consistency • Enable frequent users to use shortcut • Offer informative feedback • Design dialogues to yield closure • Offer simple error handling • Permit easy reversal of actions • Support internal locus of control • Reduce short-term memory load

22. Heuristic Evaluation • A sample problem (telephone banking) Enter ‘1’ for account info. ‘3’ for transfers '3#'

23. Heuristic Evaluation • A sample problem (telephone banking) Enter account to transfer from '12345#'

24. Heuristic Evaluation • A sample problem (telephone banking) Enter account to transfer to '#' (an abbreviation for the checking account)

25. Heuristic Evaluation • A sample problem (telephone banking) Enter amount in cents '100000#'

26. Heuristic Evaluation • A sample problem (telephone banking) From account number 12345 to account Number primary account, a transfer of 1000 dollars is to be made. Press ‘1’ to Confirm, ‘0’ to cancel. '1#'

27. Heuristic Evaluation • A sample problem (telephone banking) You do not have access to use this function

28. Heuristic Evaluation • A sample problem (telephone banking)

29. Heuristic Evaluation • Ten usability guidelines from Nielsen (1994) • Visibility of system status • Match between system and real world • User control and freedom • Consistency and standards • Error prevention • Recognition rather than recall • Flexibility and efficiency of use • Aesthetic and minimalist design • Help users recognize, diagnose, and recover from errors • Help and documentation

30. Heuristic Evaluation • Improving usability problem reports (Jeffries 1994) • Describe the problem and the solution separately • Provide justifications for the problem and the solution • Include an assessment of the severity of the problem • Explicitly consider possible trade-offs • Evaluate carefully any solution that requires new functionality to be added to the application • Try to look at each problem from multiple levels of abstraction • Examine the problem reports as a collection, replacing local optimizations and trade-offs with general solutions that fit the application as a whole

31. Additional Materials • SIGCHI • Great Online Library of Resources for Members • e.g. Rosenbaum, Rohn, and Homburg. A Toolkit for Strategic Usability. 2000. CHI Letters.

32. Additional Materials • Brooks, Frederick. “No Silver Bullet” • Our text refers to there being no “silver-bullet” process for designing and evaluating interfaces (p. 73). • This is a reference to Brooks’ paper where he suggests that there will be no order of magnitude improvement in software design (termed "silver bullet") in the next 20 years. • Designing complex systems is inherently difficult.

33. Additional Materials • Cooper, Alan. 1999. The Inmates are Running the Asylum • Engineers are an atypical specimen. • Interaction Design must separate itself from engineering. • Engineering roles are concerned with implementation details while design roles are concerned with user goals.

34. Activity and Discussion • Introduce the activity. • Split class into three groups. • Give information to groups. • Groups work on for approx. 8-10 minutes. Sketch or verbally describe the resulting design. • One person from each group present the design to the class. • Class discussion

35. Thank You • Remember: • The user • To evaluate • To Iterate • Have a nice day!