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19 The evaluation of accessibility, usability, and user experience…

- - - - disabilities & older people
    - - students in biology
- - - - ISO 9241
        
        The extent to which a product [service or environment] can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use.
        
        :check: Effectiveness
        
        :check: efficiency
        
        :check: satisfaction
      - many practitioners
        
        Gould and Lewis 1985; Shackel, 1990; 1991; Sharp, Rogers and Preece 2007; Stone et al. 2005
        
        :check: flexibility
        
        :check: learnability
        
        :check: memorability
        
        :check: safety
      - show
        
        :check: users
        
        :check: goals
        
        :check: contexts
    - - ISO 9241-171
        
        the usability of a product, service, environment or facility by people with the widest range of capabilities
        
        :check: usability is a sub-set of accessibility
      - WAI
        
        people with disabilities can use the Web. More specifically, Web accessibility means that people with disabilities can perceive, understand, navigate, and interact with the Web
        
        :check: accessibility as a sub-set of usability
      - now
        
        usability -> mainstream (i.e. non-disabled, younger) users
        
        accessibility -> disabled and older users
    - - Norman
        
        user experience, initially popularized by him in 1998
        
        users’ interactions with, and reactions to, eSystems that go beyond effectiveness, efficiency, and conventional interpretations of satisfaction.
      - Hassenzah
        
        :check: Holistic
        
        task-oriented aspects
        
        other non-task oriented aspects (hedonic aspects)
        
        beauty
        
        challenge
        
        stimulation
        
        self-expression
        
        :check: Subjective
        
        usability (objective)
        
        percentage of tasks achieved for effectiveness
        
        task completion times and error rates for efficiency
        
        UX (sujective)
        
        users’ subjective reactions to eSystem
        
        their perceptions of the eSystems
        
        their interaction with them
        
        :check: Positive
        
        usability (negative)
        
        removal of barriers or problems
        
        UX (positive)
        
        maximize positive aspects of eSystem
      - Dillon (2001)
        
        :check: Process
        
        an understanding of users’ moves, attention and difficulties through an eSystem
        
        :check: Outcomes
        
        an understanding of what it means for the user to feel accomplishment or closure with the eSystem
        
        :check: affect
        
        an understanding of users’ emotional interaction with eSystems and what interaction means for users
      - Bevan (2008)
        
        :check: Likability
        
        :check: Pleasure
        
        :check: Comfort
        
        :check: Trust
      - outline
        
        important part of evaluating eSystem & more important in the future
      - new ISO Draft International Standard 9241-210
        
        A person's perceptions and responses that result from the use or anticipated use of a product, system or service
- - - - methods
        
        :check: study existing guidelines
        
        :check: interview current & potential users
        
        :check: conduct an ethnographic & context of use
      - record in a user requirements document
        
        track subsequent design & development
        
        update to reflect changes in understanding user requirements
      - Common Industry Specification for Usability Requirements
    - - :check: explore the design space
      - :red_cross: immediately settling on one design
    - - forms
        
        simple & complex
        
        sketches on paper & animations with interactivity
      - purpose
        
        people involve in evaluation
        
        address functionality of eSystem
        
        explore particular design problems
        
        whether feasible or not
        
        feed back into design process
    - - usability, accessibility and user experience
      - :check: evaluation in real context
      - feed back
        
        understanding users
        
        design process
        
        this version & subsequent versions
    - - :star: heart of the process
      - can be done by
        
        experts
        
        users
      - purpose
        
        track
        
        feed back
      - people are such complex entities
      - process
        
        20+ iterations
        
        main design & development -> a month -> 3~4 iteration
        
        preparation -> long time -> 15+ iterations
        
        go on in parallel with back-end development
  - - - :red_cross: consider accessibility in the end -> impossible & cost max
      - :check: consider accessibility from beginning -> cost min
    - - :check: universal design
        
        the design of products and environments to be usable by all people, to the greatest extent possible, without the need for adaptation or specialized design.
      - :check: design for all
      - :check: barrier free design
      - :check: inclusive design
    - - :red_cross: can't be met in practice
      - :red_cross: frighten designers and developers
      - :check: not need to solve all the accessibility problems
    - - :check: screen readers
      - :check: screen magnification programs
      - :check: a variety of alternative input devices
      - :check: ...
    - - :check: don't use an assistive technology
      - :check: do use an assistive technology
      - :check: can not use the system without an assistive technology
- - - - IBM
        
        Software •
        Websites and applications
        Java applications
        Lotus notes
        Hardware
        Documentation
        
        Human Ability and Accessibility Centre
      - 3 ISO standards
        
        :check: ISO/IEC 610779 (2008d) -> Office equipment accessibility guidelines for elderly persons and persons with disabilities
        
        :check: ISO 9241-20 (2008a) -> Ergonomics of human-system interaction – Part 20: Accessibility guidelines for information/communication technology (ICT) equipment and services
        
        :check: ISO 9241-171 (2008b) -> Ergonomics of human-system interaction – Part 171: Guidance on software accessibility
      - WAI
        
        WCAG 1.0 1999
        
        P1 & P2 & P3
        
        14 high level accessibility guidelines
        
        65 specific checkpoints
        
        WCAG 2.0 2008
        
        A & AA & AAA
        
        :check: perceivable
        
        :check: operable
        
        :check: understandable
        
        :check: robust
      - Section 508
        
        Section 508 of the Rehabilitation Act of the United States Federal government
      - technologies
        
        :check: Adobe Flash™
        
        Regan (2004) and resources at the Adobe Accessibility Resource Centre
        
        :check: Content Management Systems Joomla!
        
        O’Connor (2007)
        
        :check: Eclipse open source development platform
        
        Accessibility Features in Eclipse 9and the Eclipse Accessibility Tools Framework Project
        
        :check: Java
        
        resources at Sun Accessibility 11
        
        :check: Microsoft™ products
        
        resources at the Microsoft Accessibility Developer Center
    - - Nielsen
        
        :check: Visibility of system status
        
        :check: Match between system and the real world
        
        :check: User control and freedom
        
        :check: Consistency and standards
        
        :check: Error prevention
        
        :check: Recognition rather than recall
        
        :check: Flexibility and efficiency of use
        
        :check: Aesthetic and minimalist design
        
        :check: Help users recognize, diagnose, and recover from errors
        
        :check: Help and documentation
      - Shneiderman
        
        :check: Strive for consistency
        
        :check: Enable frequent users to use shortcuts
        
        :check: Offer informative feedback
        
        :check: Design dialogue to yield closure
        
        :check: Offer simple error handling
        
        :check: Permit easy reversal of actions
        
        :check: Support internal locus of control
        
        :check: Reduce short-term memory load
      - U.S. Government Department of Health and Human Services (HHS)
        
        207 guidelines
        
        more complete and easier to use than the equivalent ISO
      - ISO 9241 standard
        
        very time consuming to employ in evaluation
        
        need to be interpreted in relation to a particular interface environment
    - - problems
        
        :check: learn -> large number of guidelines & efforts
        
        :check: evaluation -> time consuming
        
        :check: general guidelines -> not apply particular circumstances
        
        :check: difficult to apply without experience in application domain
      - user testing
        
        :check: user type
        
        :check: task
        
        :green_cross: environmental conditions
      - rating & accessibility issue
        
        no correlation in the ratings given by both disabled and mainstream users of actual problems
  - - - not contain basic accessibility and usability problems
    - - :red_cross: Bobby Tool -> no longer available
      - :red_cross: Many WCAG Checkpoints cannot be checked automatically -> 23% can
      - :red_cross: no automatic tool can check whether the alternative descriptions are accurate and useful
        blabla -> forgotten placeholder
        elephant -> cat mistake placeholder
        person at computer -> why include the image
    - - :check: LIFT
      - :check: Web Static Analyzer Tool
      - :red_cross: basic problems & limited scope of usability issues
  - - - identify more accessibility issues before user-based evaluations
      - too many pages / screens to user-based evaluation
      - not possible to obtain actual users
      - insufficient time for user testing
      - train developers
    - - :check: non task scenario
        
        review
        
        inspection
      - :check: task scenario
        
        walkthrough
    - - a small set of evaluators -> potential usability problems -> Cello evaluation
      - :check: evaluators
        :check: a set of heuristics
        :check: rate the potential problems individually -> how severe
        :check: a four level rating scheme is used (1,2,3,4)
        :check: better results are obtained by trained experts
      - :check: asking the evaluator to step through typical user tasks
        heuristic evaluation + cognitive walkthrough
      - :check: heuristics are a useful training aid & value is not clear
    - - identifies problems while attempting to achieve tasks in the same way as a user
      - :check: Cognitive walkthrough
        
        each user action -> evaluator analyses
        interface
        feedback
      - :check: Pluralistic walkthrough
        
        user & developer & human factor people
        
        a scenario & discuss & dialogue
    - - :check: websites and web-based applications
        
        Heuristic evaluation
        
        Expert Walkthrough Evaluations
      - :check: other types of eSystems
        
        on an ad hoc basis by an expert
        
        employ user evaluation instead
      - preliminary accessibility review
        
        :check: a representative set of pages
        
        :check: a range of graphical browsers
        
        turn off images
        
        turn off the sound
        
        use browser controls to vary font-size
        
        test with different screen resolution
        
        change the display colour to greyscale
        
        without using the mouse
      - tool
        
        :check: IE & Opera
        
        AIS Toolbar
        
        :check: Firefox
        
        Accessibar add-on
        
        WAVE Toolbar
        
        :check: Screenreader
        
        JAWS
        
        WindowEyes
      - period
        
        begin
        
        preliminary accessibility review can guide the further development
        
        complete
        
        a full accessibility audit
      - :star: Unified Web Evaluation Methodology
        
        :check: a standard reporting format for accessibility evaluation reports
        
        :check: UWEM and WAI websites
  - - - models can be constructed economically
      - user testing is not practical
    - - time to complete tasks is critical
      - other methods are impracticable
      - information provided by the model is a effective way to managing risks
    - - :check: Keystroke Level Model
      - :check: Goals Operators Methods and Selections (GOMS) model
      - :check: ACT-R model
  - - - :check: max -> all stages of development,
      - :check: min -> the final stage of development
    - - users
      - developers & managers
    - - :check: no way to find all usability issues in one evaluation
      - sample size
        
        :check: previous similar usability evaluation
        
        :check: initial results of an ongoing study
      - probabilities
        
        :check: 0.08~0.42
        
        :check: 3~19 -> 80% problems
        
        :check: 4~28 -> 90% problems
        
        :check: complex website -> lower probabilities
      - process
        
        :check: Iterative testing with small numbers of participants is preferable
        
        :check: test with at least 8 users
      - type
        
        :check: formative
        
        Formative methods focus on understanding the user’s behaviour, intentions and expectations in order to understand any problems encountered, and typically employ a “think-aloud” protocol;
        
        :check: summative
        
        Summative methods measure the product usability or accessibility, and can be used to establish and test user requirements
    - - ways
        
        :check:remote evaluation
        
        :check: simulate users with disabilities -> disabled develop strategies to deal with problems -> not comparable
      - consider
        
        :check: assistive technology
        
        :check: expensive & time consuming -> remote testing instead
        
        :check: the needs of participants in the evaluation
        
        :check: how will they come
        
        :check: the location accessible
        
        :check: explanatory material & consent forms -> alternative formats
        
        :check: pace of evaluation suitable
    - - :check: Kansei techniques
      - :check: rating scales and questionnaires -> simplest
      - :check: Psychometrically designed questionnaires -> SUS -> usability
      - :check: AttrakDiff -> user experience
  - - - improve an existing eSystem
    - - Provides non-intrusive data
    - - economical & feedback
    - - entrance and exit pages
      - frequency of particular paths through the site
      - the extent to which search it successful
      - difficult to track individual behaviour
      - particular user groups and tasks
    - - data point
      - anonymously to developer
      - guide future design decision