Universal Access to Technology

User-centered system Design is iterative!

DESIGN TEST

Case Study:

Computer Aided Conversation for Severely Physically

Impaired Non-speaking People

(Norman Alm et al.)

Why I like this article

Solves a real problem Tells a clear story Did a terrific analysis of the task Technical solution is informed by a

theory of communication Good evaluation at the end

Conversation

Turn-taking Adjacency pairs Topic structure Perspectives

What the researchers did:

Task analysisHad real user in mindSimulation with index cardsRole playing Iteration

Screen design Evaluation

Healthy usersNon-speaking user

Computer-assisted conversationA: I went to France last year, to Marseilles. B: I’ve never visited Marseilles, I’ve sort of driven round

the outskirts, but never actually gone into Marseilles. A: Surprisingly, it’s really beautiful. B: Really? I just imagine it as sort of a port, and just like

any other large city, with nothing particularly interesting.A: You expect a major port to be fairly grotty, don’t you ?B: [LAUGHl That’s right [LAUGH].A: We also visited other places on the coast, but we decided

to give St. Tropez a miss.B: That’s one place I’d like to go.A: I’ve heard it’s pretty grotty now, and crowded.B: Really ? Oh, well, maybe give it a miss then. Of course,

there’s always the chance to see Brigitte Bardot there.A: Whatever turns you on.

What’s the web like if you can’t see it?

A point of view by Chieko Asakawa

Section 508 of the Rehabilitation Act: All federal agencies must make their info available to people with disabilities

How? Screen readers, alt texts, skip-navigation links

More and more images, with more and more “alt texts”

What’s the web like if you can’t see it?

“These days, Web pages are becoming larger and visually more complex using layout tables, images, colors and other visual effects. Thus, one page contains more various types of information than ever before. This means that blind users need to spend more time on one page to extract the information they need, since voice browsers (in this discussion, voice browser means both self-talking browsers and screen readers) present information serially using a text-to-speech (TTS) engine.”

(from Asakawa, 2005)

Skip navigation link

Alt text

The irony: sometimes the very features meant to make the page more accessible actually makeit worse

Asakawa’s example of empty images used to space real images: With no alt text, these were invisible to her. With alt text added, she had to listen to lots of “spacer gif” readouts!

Some ways of improving accessibility:

Guidelines, legislation, and standards (skip links, content anchors, alt text, etc.)

Have sighted designers experience a web page as the blind do! aDesigner - simulates blind experience Estimates “reaching times” for key parts of page

aDesigner

Inaccessible parts are darkened

Some ways of improving accessibility:

Guidelines, legislation, and standards (skip links, content anchors, alt text, etc.)

Have sighted designers experience a web page as the blind do! aDesigner - simulates blind experience Estimates “reaching times” for key parts of page

“Intelligent” parsing of web pages (HearSay) Treat form-filling as a kind of dialogue

See Tony’s fax form example Include methods for repair and managing interruptions