340 likes | 466 Views
Bradley Dilger Dept of English & Journalism Western Illinois University Macomb, IL cb-dilger@wiu.edu. Defining accessibility and usability. Today’s presentation. Continue to increase role of accessibility and usability in technical communication Discuss parallels and confusion
E N D
Bradley Dilger Dept of English & Journalism Western Illinois University Macomb, IL cb-dilger@wiu.edu Defining accessibilityand usability
Today’s presentation • Continue to increase role of accessibility and usability in technical communication • Discuss parallels and confusion • Encourage thinking about definitions • Build better theory and practice, especially in education
Assumptions • Both accessibility and usability should be: • part of user-centered design and development • integrative: considered by all parties, throughout creative processes • Benefits of both far exceed legal obligations and cost
Confusion & conflation • Often good intentions • Several sources: • unfortunate parallels • oversimplified definitions • simple conflation
Unfortunate parallels • Address one and you address the other • Solely technological • For disabled or dumb only • Do at the end • Additive • Too much trouble • Stultifying
Parallels: definitions • Often simplified, even oversimplified • Lack of consensus about specifics • Often conflicting
“The ease of which a user can interpret and respond to information.” “A set of properties that makes something easy to use.” “An evaluation and measurement of a computer program's overall ease-of-use.” Usability = ease
Defining accessibility • Wide variation in form and content • Giorgio Brajnik’s review: • WCAG 1.0, 2.0 have none • Two in Italian law • Slatin & Rush • ISO 16071: usability • Henry: primarily usability
Accessibility = usability? • Nielsen: “When you want to improve your website for users with disabilities, remember the real goal: to help them better use the site. Accessibility is a necessary, but not nearly sufficient, objective. Your main focus should be on the site's usability for disabled users, with an emphasis on how well the design helps them accomplish typical tasks.”
A subset? • Is accessibility part of usability? • Henry and others
A precursor? • Is accessibility a precursor to usability? Or vice-versa? • Accessibility is a precursor to usability. If a product is inaccessible it is, by definition, unusable since you cannot get access to it.... Once access to a product is made, the question of its usability can be determined. (Killam qtd in Clark)
Recap of problem • Parallels, many negative, encourage conflation of accessibility and usability • Unstable and often too simple definitions—reinforced by parallels
Solution • Be more careful about parallels • Clarify relationship • Clarify definitions
Fixing parallels • Continue to attack negative parallels • Emphasize positive • Avoid temptation to combine accessibility and usability for convenience • institutions • process • education
Fixing relationship • Neither equivalent, subset, precursor, technical, or limited work exclusively • All true at times • More discussion in this area needed
Fixing definitions • Attack poor definitions • Insist on role of user-centered design and development • Use multi-part definitions
Multi-part: usability • learnability, or being “easy to learn” • efficiency of use • memorability, or “an interface that is easy to remember” • few and noncatastrophic errors • subjective satisfaction, or pleasure in use • Nielsen 1993; Quesenbery similar
Multipart: accessibility • WCAG 2.0 (Henry et al.): • perceivable, operable, and understandable • robust • navigable • POUR or PONUR
Multipart: accessibility • Principles of universal design: • Equitable Use • Flexibility in Use • Simple and Intuitive Use • Perceptible Information • Tolerance for Error • Low Physical Effort • Size and Space for Approach and Use
Why multipart? • WCAG 2.0 • Facilitates comparison of accessibility and usability • Allows weighting parts of definition pending context • Ideal for variety of situations encountered by technical communicators • Supports integrative approach
Which multipart? • PO(N)UR • Principles of universal design • Other concepts • equivalence • flexibility (“transformability”) • affordance
The future • WCAG 2.0 • More computing, so more need for accessibility and usability • Emergent technologies still have questionable accessibility: AJAX • Aging population means more need for accessibility
Link to presentation: http://faculty.wiu.edu/CB-Dilger/ Contact: cb-dilger@wiu.edu Thank you