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Re: 48-Hour Consensus Call: InstateLongdesc CP Update

From: Janina Sajka <janina@rednote.net>
Date: Wed, 19 Sep 2012 16:31:58 -0400
To: Leif H Silli <xn--mlform-iua@xn--mlform-iua.no>
Cc: mjs@apple.com, bhawkeslewis@googlemail.com, joshue.oconnor@cfit.ie, silviapfeiffer1@gmail.com, faulkner.steve@gmail.com, john@foliot.ca, rubys@intertwingly.net, public-html-a11y@w3.org
Message-ID: <20120919203158.GA21218@opera.rednote.net>
Leif H Silli writes:
> Maciej, e.g. Janina did not reject Steve's findings. She only
> questioned their relevance. It would be more interesting - now - to
> conclude about: how to interpret the misuse and why it is negative
> or does not matter. Leif
> 

This is correct--thanks, Leif. In particular we have a scientific study
of the efficacy of (long) textual descriptions of graphics comparing
several modalities:

http://ncam.wgbh.org/experience_learn/educational_media/stemdx#top

I submit the findings of this kind of study are far more useful than a
random collection of incidental usage in the wild.

The use being made of longdesc in educational settings in the U.S.
particularly is systematic, extensive, and invisible to the casual
observer because it exists behind copyright restrictions. It also
succeeds despite the lack of support from browser developers which we
keep hearing about here. Even without the major vendors, people are
finding value in this HTML 4 attribute today--value which HTML 5 has not
replaced.

Janina

> 
> ------- Opprinnelig melding -------
> >Fra: Maciej Stachowiak <mjs@apple.com>
> >Til: bhawkeslewis@googlemail.com
> >Cc: joshue.oconnor@cfit.ie, xn--mlform-iua@xn--mlform-iua.no,
> >silviapfeiffer1@gmail.com, faulkner.steve@gmail.com,
> >john@foliot.ca, rubys@intertwingly.net, public-html-a11y@w3.org
> >Sendt: 19/9/'12,  18:43
> >
> >
> >On Sep 19, 2012, at 3:11 AM, Benjamin Hawkes-Lewis
> ><bhawkeslewis@googlemail.com> wrote:
> >
> >>On Wed, Sep 19, 2012 at 11:07 AM, Joshue O Connor
> >><joshue.oconnor@cfit.ie> wrote:
> >>>>I did not have time too look through it, but those I looked at either
> >>>>contained only a "#" or they contained (another) image file. With
> >>>>regard to the first (#) then I agree "misinformed" about the potential
> >>>>negative effect. With regard to image URLs inside @longdesc,
> >>>>then there
> >>>>are image light box solutions - libraries - that  more or less
> >>>>consciously makes incorrect use of longdesc. (Today they would perhaps
> >>>>picked at @data-foo attribute instead - but that was not
> >>>>'valid' then.)
> >>>>Of the few I scanned, no one contained text.
> >>>
> >>>
> >>>Yikes, maybe it is the former Silvia. Thanks for doing that
> >>>Leif. It does
> >>>therefore sound like an inappropriate sample population or at least
> >>>partially so.
> >>
> >>How does the reason why longdesc was misused make it in an
> >>inappropriate sample population for client software developers trying
> >>to make a decision about whether to expose longdesc via UI to their
> >>users?
> >>
> >>(My problem with these approaches to sampling is that randomly
> >>sampling the web corpus doesn't match the pattern of usage by typical
> >>users, it just tells you about long tail effects, so the relationship
> >>with user impact is unclear.)
> >
> >Some browser vendors (including Apple) have the ability to gather
> >data on real-world usage as actually observed by users. Generally
> >for privacy considerations we cannot log individual URLs. But we
> >could log data such as:
> >
> >- What proportion of images have a longdesc attribute
> >- What proportion of those images have obviously wrong longdesc
> >URLs (empty, #, appears to be an image, top-level URL of a domain,
> >url of the same page that contains the image, etc)
> >
> >Would folks see such data as more credible? It would be
> >significant effort and we could not reveal the raw numbers. I
> >suspect many would reject such data as not publicly reproducible.
> >
> >Regards,
> >Maciej
> >
> >

-- 

Janina Sajka,	Phone:	+1.443.300.2200
			sip:janina@asterisk.rednote.net
		Email:	janina@rednote.net

The Linux Foundation
Chair, Open Accessibility:	http://a11y.org

The World Wide Web Consortium (W3C), Web Accessibility Initiative (WAI)
Chair,	Protocols & Formats	http://www.w3.org/wai/pf
	Indie UI			http://www.w3.org/WAI/IndieUI/
Received on Wednesday, 19 September 2012 20:32:36 GMT

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