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Re: Switches and Universal Access

From: philip steven lanier <planier@u.washington.edu>
Date: Wed, 15 Jan 2003 12:44:15 -0800 (PST)
cc: w3c-wai-ig@w3.org
Message-ID: <Pine.A41.4.44.0301151145110.97216-100000@dante54.u.washington.edu>

Johnathan,
A couple points:

1) I am not at all surprised that the videos on the DO-IT site assume a
somewhat greater ability than the population you are describing.  Keep in
mind the audience for the videos.  I would assume that there are very few
individuals at the university level who have severe learning disabilities.

2) To quote:
> "To imagine the problems facing switch users consider typing an email,
> that's 26 clicks for every letter or say 100 per word..."

Most systems that use a switch (aside from those that use morse code),
usually rely on scanning.  This typically employs a "divide and conquer"
strategy to select keys on the keyboard: A moving cursor highlights
different parts of the keyboard, and as the user selects these, the area
of focus gets incresingly narrower until the user selects the key he/she
wants.  This means that the user often has to click 2-4 times per letter
(as opposed to 26 times), and the selection moves perhaps 5-10 times.
(This is a rough guess, if anybody cares to correct me.)  Not to say that
this is at all easy or efficient, but I don't think it's accurate to say
that the typical switch user must click 26 times per letter.

> "(predictive software could possibly help a little, though users might
> have problems selecting words that were unfamiliar) now imagine you also
> have a physical and or cognitive impairment."

In my experience, predictive software can help *significantly* for many
switch users.  The one case where it may not help, as you alluded to, is
the case where the user does not understand how to use the word prediction
software.  (I.e. the software is too complex for the user to learn.)

3) The issues with the sites you discuss are perhaps slightly more
complex.  For one, I think the BBC site has some major *usability* issues.
Accessibility issues aside, other than for site indexes, a page with 160
links is rarely ideal.  The BBC site also has some major linearization
issues (associated with the incorrect use of tables for layout).  The
other site you discuss (peepo.com) is very unique in that it is
*specifically* for online radio listeners who have severe learning
difficulties and who use switches.  In fact, for most other audiences, the
site would be very unusable, and for many people with disabilities it
would also have accessibility problems.  In this regard, I think it could
be useful to differentiate between a site such as this and another general
site that is "regularly check[ed]... for 'switch' accessibility."


In any case, I do recognize that your ultimate question/issue was that
"a switch site has been asked for" and you are considering how best to
develop this.  Unfortunatly, I do not have the answer.  I did want to try
to clear a few things up, however.  I also hope that the links I provided
were helpful to those who had no idea what switches are and how they're
used.  I will be looking forward to hearing what suggestions others have
regarding a site specifically for switch users, and I am also looking
forward to seeing what solution(s) you come up with.  Keep us informed!

Philip Lanier
University of Washington
Senior, Informatics




On Wed, 15 Jan 2003, Jonathan Chetwynd wrote:

>
> Philip & Jukka,
>
> Our users* have severe learning difficulties. The video: 'Working
> Together: Computers and People with Learning Disabilities'
> http://www.washington.edu/doit/Video/wt_learn.html assumes a somewhat
> greater ability. This applies to the other resources I viewed on the
> Washington University site.
>
> To imagine the problems facing switch users consider typing an email,
> that's 26 clicks for every letter or say 100 per word, (predictive
> software could possibly help a little, though users might have problems
> selecting words that were unfamiliar ) now imagine you also have a
> physical  and or cognitive impairment.
>
> The BBC radio site: http://www.bbc.co.uk/radio/ has 160 links, last
> time I counted, think on this. try it out using a tab switch.
> Now visit http://www.peepo.com/alfy/radio/b.html type a letter, or tab
> through the alphabet. potentially 260 radio stations within 46 clicks.
> Can someone else improve on this?
>
> The web currently offers very little for this community, and very few
> every get paid employment.
> We are still a very long way from enabling people with severe learning
> difficulties using (adaptive) technology.
>
> thanks
>
> Jonathan
>
> *many of our users respond to concrete symbols, ie TV, microwave...most
> recognise photographs of people they know(of) telling the time is a
> significant achievement, as would 'simple' addition be, some follow
> soaps, and many have special interests about which they know much. We
> do have a few users who can read plain simple English in a ~20pt font,
> and we intend to add the option of a text label to links at
> http://www.peepo.com, this only allows 5 or 6 letters so has its own
> problems. If you mouse over there is a tooltip, and the font size can
> be set much larger.
>
> A switch site has been asked for, and we are considering how best to
> develop this......
>
>
Received on Wednesday, 15 January 2003 15:44:18 GMT

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