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Re: 48-Hour Consensus Call: InstateLongdesc CP Update

From: Maciej Stachowiak <mjs@apple.com>
Date: Wed, 19 Sep 2012 09:43:39 -0700
Cc: Joshue O Connor <joshue.oconnor@cfit.ie>, Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>, Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Steve Faulkner <faulkner.steve@gmail.com>, John Foliot <john@foliot.ca>, Sam Ruby <rubys@intertwingly.net>, public-html-a11y@w3.org
Message-id: <DFEA42A6-5970-497A-8B16-A5B1F29F03B1@apple.com>
To: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>

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
Received on Wednesday, 19 September 2012 16:44:30 GMT

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