Usability with Project Lecture 8 – 3/10/08

1. Usability with ProjectLecture 8 – 3/10/08 Dr. Simeon Keates

2. Exercise – part 1 • Last week you were asked to prepare a plan for testing the accessibility of your own site • This week… • …do it!

3. Exercise – part 2 • Prepare a 5 minute presentation • Address the following questions: • Did you consider accessibility issues when you designed the site? • What was your testing plan? • Which user capabilities did you test for (e.g. colour blindness)? • What further tests do you think are necessary? • With the knowledge of accessibility issues that you have gained, would you have designed the site differently if “accessibility” had been a stated design goal at the outset? If so, how? • Order of presentations: • Group 2, 4, 6, 1, 3, 5

4. Assessment of DTT STBs...

5. Service provider Remote control User Remote control Set top box (STB) A systems overview Television

6. Motivations for study • Commissioned by UK Department of Trade and Industry • Wanted to find out who could not access DTT • Original focus on ‘the disabled’ • Definition broadened... Why?

7. Typical assessment methods used in this research • Expert assessment • Exclusion analysis • User observation • Questionnaires • Interviews • Focus Groups Assessment of STBs Customer expectations

8. Methodology - Choice of STBs 2 STBs chosen for study • STB1 - marketed as “easy to use” • STB2 - market leader 1 digital satellite system chose as comparison • STB3– developed by content provider

9. Expert assessment • 4 assessors • 2 with DTV experience, 2 without • STB protocol only • Aims to identify most likely sources of problems • Define protocol for following assessments

10. Methodology - Analogue TV protocol • 6 activities • Switch on • Change channel • Change volume • Teletext (find local weather) • Subtitles (on/off) • Switch off

11. Methodology - STB protocol • 8 activities • Installation • Switch on • Change channels (direct + EPG) • Change volume • Teletext (find local weather) • Subtitles (on/off) • BBCi (find local weather) • Switch off

12. Expert Assessment - Results 13 major sources of difficulty found • 4 – Installation and set-up • e.g. instruction manual, initial tuning • 5 – Operation • e.g. multiple modes, subtitles • 4 – Remote controls • e.g. labelling, layout

13. Exclusion analysis • Systematic analysis • Combined with data from Office of National Statistics • Population data 1996/7 UK Disability Follow-Up Survey • Aims to calculate how many people have the difficulties highlighted by expert assessment • How many people in the user observation should have those difficulties?

14. Example – breakdown of installation

15. Exclusion analysis - Results 16+ 75+ 25 20 Population (,000s) 15 10 5 0 Analogue DTV Analogue DTV

16. Exclusion analysis - Results 16+ 75+ 25 25 20 20 Population (,000s) Population (%age) 15 15 10 10 5 5 0 0 Analogue DTV Analogue DTV

17. User observations - Overview • 13 users - 12 aged 60+, 1 aged 24 • 9 no DTV experience • 2 owned STBs • 1 owned satellite box • 1 owned iDTV • 7 PC users, 6 non-users • All ‘independent’ living

18. User observations - Methodology 2 hour sessions comprising: • 30 minutes briefing • 60-75 minutes with equipment • 15-20 minutes analogue • 40-60 minutes DTV • 2 STBs • 15 minutes debriefing

19. User observations - Set-up

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27. User observations - Example visual problems • Finding buttons on r/c • Especially POWER • Switching between r/c and screen • Different pairs of glasses • Reading on-screen font • No zoom facility • Reading instruction manual • Small print New difficulty

28. User observations - Example motor problems • Pressing buttons on r/c • Size and shape • Time-outs • e.g. on EPG (040 -> 004) • Arrow button overshoot • Oscillating cursor New difficulty New difficulty

29. STB2 remote control

30. STB1 remote control

31. User observations - Example ‘cognitive’ problems • Use of OK/SELECT • Inconsistent language (OK=SELECT?) • Which r/c to use / which mode am I in? • How to start/navigate BBCi/Teletext? • How to call up/navigate on-screen menus? • How to operate/navigate the EPG? • Inconsistent layout • e.g. LHS on screen, RHS on r/c

32. User observations - Summary of results

33. Summary • Cognitive/experience issues most important • Many of the problems easily avoidable

34. Classic case of “designers designing for themselves” Origins of the problems for older users • New language / terminology • Jargon • New input paradigms • Part TV, part PC • New interaction concept • Interacting with STB, not TV • Inadequate explanation

35. Implications of prevalence of cognitive difficulties • What does this mean for assessment methods? • Single assessment methods vs. multiple? • In what order should they be used? • What does this mean for designers? • How to design for different experience?

36. Designing for cognitive support

37. Background • International Symposium • Held in October 2005 • Venue: IBM TJ Watson Research Center • Sponsored by: IBM HA & AC • 10 invited experts • Data presented here from that Symposium

38. No single, clear definition. Mostly focused on what users cannot do Defining C&LDs • US medical community definition • “A cognitive disability arises from an impairment that affects IQ” • i.e. effects capability to acquire, process and utilise knowledge • Arises from how medical conditions are diagnosed and treated • Educators focus on learning difficulties • Often focused on educational attainment • Do behavioural difficulties count? • Some say yes, some say no

39. Defining C&LDs for UI design • Alternative definition needed for UI design • Need to understand what users are capable of • Not what they cannot do • Need functional descriptions of capabilities • Descriptions tailored to design project

40. Prevalence of C&LDs - US statistics • When asked • “Have you had a physical, mental or emotional condition lasting 6 months or more that made it difficult to learn, remember or concentrate” • 5.2% of all US adults agreed • (Source: 1999-2004 American Community Survey)

41. Figures from both surveys are most likely conservative Prevalence of C&LDs - GB statistics • 5.6% of GB adults self-report some form of cognitive impairment • (Source: 1996 Disability Follow-Up Survey) • “Cognitive impairment” comprised of: • Communication • E.g. “Has some difficulty understanding what other people say or what they mean” • Intellectual Functioning • E.g. “Often forgets what was supposed to be doing in the middle of something”

42. Role of cognition in interaction • Model Human Processor (Card, Moran and Newell) F(t) = xp + yc + zm where • p = perceptual time unit • c = cognitive time unit • m = motor function time unit • x, y, z are integers

43. Role of cognition (cont.) - Simplex II • “Cognition” comprises: • Working memory • Emotions and drives • Perception • Output • Feedback • Complex output sequences • Cognitive models • Long-term memory • Executive functions (Adams)

44. Can be assisted by “design best practices” Why C&LDs are not commonly addressed in UA… • They are often difficult to diagnose • Perception issues are easy to diagnose, cognitive ones are not • Many do not have a “universal” diagnosis • E.g. what exactly is dyslexia? • Many people with them are reluctant to admit this • The “invisible” impairment - stigma • Designing for them is not easy • No clear description of C&LD makes design more difficult

45. The more designers know about their users, the better their designs become 1 - Involve users in design process • “Standard” UA advice • Can act as design partners • Working with designers • User study participants • Issues regarding ethical approval

46. Designers should ensure that IT system demands are no more than the task demands 2 - Find required set of demands to complete the task • Every task has associated capability demands • Writing a letter, using an ATM, etc. • Every IT system has associated capability demands • Navigation, interaction, etc.

47. New concept The more references to existing knowledge, the more stable the new knowledge Existing concept Existing concept Existing concept Existing concept 3 - Use scaffolding techniques • New concepts need to be supported in multiple ways New concept

48. 4 - Use positive reinforcement • Many people with C&LD have low self-esteem • Perceived stigma • Often branded as “failures” or “thick” as children • Are used to being “judged” • IT is attractive because it is not so quick to “label” • Designers need to build on this perception • Avoid negative comments • Provide positive support and reinforcement

49. Relate new concepts to familiar ones Use multiple modalities 5 - Design for user’s learning strengths • Not everyone has uniform C&LDs • Need to design to user strengths, e.g. … • Older adults • often have poor “dynamic” memory • often have good “crystalline” memory • People with dyslexia • written instructions hard to follow • visual / auditory instructions easy to follow

50. Save Print File Edit Format File Edit View Insert Format Tools Allow users to proceed at their own pace 6 - Design for flexibility • E.g.: Offer sliding scales of complexity Basic word processor Mid-level word processor High-level word processor