Creating User Interfaces Usability Rules. Fitts's Law Homework: Choose government site. Prepare to present/discuss in class.

Accessibility U of Alaska mathematics Discussion?

Usability rules Jakob Nielsen's rules: http://www.useit.com/papers/heuristic/heuristic_list.html Heuristics for mobile phones: http://www.iphoneuxreviews.com/?p=114 Yours?

Error prevention I also call this offensive practices. Examples: pull-down lists of months, days, years, rather than open text. Can also force dates in the future dulling/fading illegal options ???

Error recovery Errors do happen. Make detection early, quick, efficient catch as many errors as possible each time, not one at a time IF POSSIBLE Use confirmation screens

New NY voting machines People mark ballots (fill in the circle) and feed into optical readers. Advantage: paper record. Disadvantages: no confirmation whole ballot can be rejected if over-voting (but no clue as to what) less than private ?

Adaptability Provide alternatives for new versus experienced users. Examples: shortcut keys on many applications reduced menus (AutoCad example) ?

Recognition versus recall Show list of recent and/or most popular choices, changed as user types so user can select. ?

Fitts's Law Time to get to a place on the screen is dependent on the distance and the precision required. Confirmed by actual testing! T = k log2(D/S + 0.5), k ~ 100 msec. T = time to move the hand to a target D = distance between hand and target S = size of target http://www.usabilityfirst.com/glossary/term_265.txl http://ei.cs.vt.edu/~cs5724/g1/glance.html Not much hard science in usability but here is something!

Group exercise http://www.asktog.com/columns/022DesignedToGiveFitts.html

Cautionary note Skills at using screen, mouse, touch pad, etc. changing, evolving Skill at typing (regular) text is….degrading? Discuss

Predictive text Opinions? What do you generally do? Some predictive text is adaptive….

Reprise: Stories People coming into ER complaining of abdominal pain Researcher did not want natural language best/satisfactory interface MAY be different than automation of manual method interface needs to fit the data/problem. Early IBM multimedia lessons (Ulysses, Columbus, etc.) Complaints of system too slow, but wasn't it more lack of keywords, descriptions, etc. leading to the wrong video clip. Case of 'advanced technology' not being as effective as other methodology.

Also: expectations / experiences What users bring to [your] application is important: Experiences with other (existing) platforms and applications Expectations on what [your thing] will be For example, this should take one mouse click versus I need to enter considerable amount of complex data. The process can and should be … deliberate, much feedback.

Homework Find a government site (one of your representatives, healthcare.gov, stimulus?) Decide on target audiences, typical questions. Try it! Prepare to present.