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Evaluation (cont.): Heuristic Evaluation Cognitive Walkthrough. CS352. Announcements. Presentations of user studies Mon 7/12 (15-20 min each group) Project – Concepts and Prototypes due next Thu 7/15 at 11:59pm (presentation next day in class) Reading: Heuristic Eval : Read 15.2
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Evaluation (cont.):Heuristic EvaluationCognitive Walkthrough CS352
Announcements • Presentations of user studies Mon 7/12 (15-20 min each group) • Project – Concepts and Prototypes due next Thu 7/15 at 11:59pm (presentation next day in class) • Reading: • Heuristic Eval: Read 15.2 • Cognitive Walkthrough (first-time users): Read 15.3
Where we are in PRICPE • Predispositions: Did this in Project Proposal. • RI: Research was studying users. Hopefully led to Insights. • CP: Concept and initial (very low-fi) Prototypes due Monday of Week #6. Evaluate throughout, repeat iteratively!!
Review • Analytical vs. empirical evaluations • Examples of analytical evaluations? • GOMS • KLM
Evaluation • Analytical – based on your head • Empirical – based on data • Formative • inFORMs design • what is (still) needed? • Summative • did it work?
Analytical methods • You follow established guidelines/procedures/models to decide (in your head) how good your design is. • Examples: • GOMS/KLM – for skilledusers. • evaluating efficiency of regular use. • Heuristic Evaluation • Cognitive Walkthrough – for first-time users. • evaluating ease of learning.
Heuristic Evaluation One of the “Discount Usability” methods • Apply heuristic guidelines (e.g., Nielsen’s) to a UI to find problems. • Who does it: • Multiple usability experts. • Default: use Nielsen’s: • http://www.useit.com/papers/heuristic/heuristic_list.html
“Discount Usability” http://www.useit.com/papers/guerrilla_hci.html
Heuristic Evaluation • One of the “Discount Usability” methods • Apply heuristic guidelines (e.g., Nielsen’s) to a UI to find problems. • Who does it: • Multiple usability experts. • Default: use Nielsen’s: • http://www.useit.com/papers/heuristic/heuristic_list.html
Nielsen’s 10 Usability Heuristics • Visibility of system status • Match between system and the real world • User control and freedom • Consistency and standards • Error prevention (e.g., default choice being “Cancel”) • Recognition rather than recall
Nielsen’s 10 Usability Heuristics (cont’d) • Flexibility and efficiency of use (e.g., short cut keys vs. menus) • Aesthetic and minimalist design
Nielsen’s 10 Usability Heuristics (cont’d) • Help users recognize, diagnose, and recover from errors • Help and documentation (but keep in mind that users do not like to read manuals)
Other examples of heuristics • Heuristics for ambient displays: • pp. 699-700. Nabaztag ambient display http://infosthetics.com/archives/2005/10/nabaztag_ambient_email_display.html
Heuristic Evaluation: How • How: • Pick some usability guidelines, experts, task. • Brief the experts. • Experts indep’ly evaluate UI’s conformance with those guidelines for that task (1-2 hrs.) • Pass 1: flow. • Pass 2: UI details. • Outcome: UI problems. • Experts meet to discuss problems, assign priorities, suggest solutions.
Activity – HE for REI.com • Heuristics for the web: • Avoid orphan pages, i.e., pages not connected to homepage • Avoid long pages with excessive white space that force scrolling • Provide navigation support, such as a strong site map that is always present • Avoid narrow, deep, hierarchical menus that force users to burrow deep into the menu structure • Avoid non-standard link colors • Provide consistent look and feel for navigation and information design • Pick any three and do a heuristic evaluation – write down problems you find
Cognitive Walkthrough • “Walk through” the UI, asking yourself questions along the way. • Who does it: • 1 or more usability experts. (3 is ideal) • How: • Identify characteristics of user and task. • Make up multiple copies of the Questions (next slide...)
Cognitive Walkthrough: How (cont.) • Walk through the task while answering these Questions: • Will the user know what to do? (Gulf of exec) • Will the user see how to do it? (Gulf of exec) • Will the user understand from feedback whether their action was correct? (Gulf of eval)
Cognitive Walkthrough: How (cont.) • Record the answers but also: • Assumptions about what would cause the problems and why. • Notes about side issues. • Notes about possible solutions. • Example for Amazon.com • pp. 703-704.
Activity • Go to rei.com • Task: buy a pair of skis • For each step, write down: • What is the user trying to do? • Answer to each of the questions: • Will the user know what to do? (Gulf of exec) • Will the user see how to do it? (Gulf of exec) • Will the user understand from feedback whether their action was correct? (Gulf of eval)
Comparison • GOMS/KLM vs. HE vs. CogWalk • how long it takes you to do • how much detail it gives you • about what kind of user