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school:classes:cs352:start [20 years ago - 2006/03/01 00:48] – aogailschool:classes:cs352:start [19 years ago - 2007/05/28 06:45] (current) – external edit 127.0.0.1
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     * Removes people variations.     * Removes people variations.
  
 +===== Heuristic Evaluation =====
  
 +==== Discount Usability Engineering ====
 +
 +  * Cheap
 +    * No special labs/equipment.
 +    * More careful you are, the better it gets.
 +  * Fast
 +    * On order of 1 day to apply.
 +    * Standard usability testing may take a week.
 +  * Easy to use
 +    * Can be taught in 2-4 hours.
 +  * Reliance on discount UE can lead to sloppiness.
 +    * Easy to ignore more thorough evaluation methods.
 +    * Not all you need.
 +
 +==== HE Overview ====
 +
 +  * Developed by Jacob Nielsen.
 +    * Involves a set of guidelines -- heuristics.
 +    * Rules come from real-world experience.
 +  * Helps find usability problems in UI design.
 +  * Small set (3-5) of evaluators examine UI.
 +    * Independently check for compliance with usability principles (heuristics).
 +    * Different evaluators will find different problems.
 +    * Evaluators only communicate afterward; findings are then aggregated.
 +  * Can perform on working UI or sketches.
 +  * Most important ideas:
 +    * Independent analysis.
 +    * Performed on sketches or UI.
 +
 +==== Process ====
 +
 +  * Evaluators go through UI several times.
 +    * Inspect various dialogue elements.
 +    * Compare with list of principles.
 +    * Consider other principles/results that come to mind.
 +  * Usability principles:
 +    * Nielsen's "heuristics".
 +    * Supplementary list of category-specific heuristics.
 +      * May come from competitive analysis & user testing of existing products.
 +  * Fixes for violations may be suggested by heuristics.
 +
 +==== Nielsen's Original 10 Heuristics ====
 +
 +  * Simple & natural dialog
 +  * Speak user's language
 +  * Minimize user's memory load
 +  * Consistency
 +  * Feedback
 +  * Clearly marked exits
 +  * Shortcuts
 +  * Precise & constructive error messages
 +  * Prevent errors
 +  * Help and documentation
 +
 +==== Heuristics -- Revised Set ====
 +
 +=== Visibility of System Status ===
 +
 +  * Keep user informed about what is going on.
 +  * Example: Pay attention to response time.
 +    * 0.1 sec: No special indicator needed.
 +    * 1.0 sec: User tends to lose track of data.
 +    * 10 sec: Max. duration if user to stay focused on action.
 +    * For longer delays, use progress bars.
 +
 +=== Match between system and real world ===
 +
 +  * Speak user's language.
 +  * Follow real world conventions.
 +
 +=== Consistency & Standards ===
 +
 +=== Aesthetic and minimalist desgin ===
 +
 +  * No irrelevant info in dialogs.
 +
 +==== HE vs. User Testing ====
 +
 +  * HE much faster.
 +  * HE doesn't require interpreting user's actions.
 +  * User testing far more accurate.
 +    * Takes into account actual users and tasks.
 +    * HE may miss problems and find false positives.
 +  * Good to alternate between HE and user testing.
 +    * Find different problems.
 +    * Don't waste participants.
 +
 +==== HE Results ====
 +
 +  * Single evaluator achieves poor results.
 +    * Only finds 35% of usability problems.
 +  * 5 evaluators find ~75% of problems.
 +    * If they work as team, it's back down to 35%.
 +  * Why not more evaluators?
 +    * Adding evaluators costs more.
 +    * Many more evaluators won't find many more problems.
 +
 +===== Evaluation (2) & Wrap-Up =====
 +
 +==== Evaluation Pt. 2 ====
 +
 +=== Usability Testing: The Usability Lab ===
 +
 +  * A specially designed room for conducting controlled experiments observing a task.
 +  * Cameras, logging systems, people track what users do.
 +  * Good lab costs $$$.
 +
 +== Observation Room ==
 +
 +  * Three cameras capture subject, subject's monitor, and composite picture.
 +  * One-way mirror plus angled glass captures light and isolates sound between rooms.
 +  * Room for several observers.
 +  * Digital mixer for mixing of input images and recording to media.
 +
 +== Other Capture - Software ==
 +
 +  * Modify software to log user actions.
 +  * Can give time-stamped keypress/mouse events -- sync with video
 +  * Commercial software available ($$$)
 +  * Two problems:
 +    * Too low level, want higher level events
 +    * Massive amount of data; need analysis tools
 +
 +== Complimentary Methods ==
 +
 +  * Talkaloud protocols
 +  * Pre/post surveys
 +  * Participant screening/normalization
 +  * Compare results to existing benchmarks