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

2. Accessibility
U of Alaska
mathematics
Discussion?

3. Usability rules
Jakob Nielsen's rules:
Heuristics for mobile phones:
Yours?

4. 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
???

5. 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

6. 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 ?

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

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

9. 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
Not much hard science in usability but here is something!

10. Group exercise

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

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

13. 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.

14. 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.

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