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Re: AW: Additional Point/Question: problem centered / page centered evaluation

From: <fischer@dias.de>
Date: Mon, 05 Sep 2011 09:41:25 +0200
Message-ID: <20110905094125.14592dfk9395r291@webmail.dias.de>
To: public-wai-evaltf@w3.org

To me, it is not at all clear what a "problem-centred" approach to web  
site accessibility evaluation actually is. I would have thought that  
the existence of WCAG success criteria means to check pages or  
processes *across the board* to to spot and record *any* problems that  
may exist, also less obvious ones. Problems become apparent only  
during those checks (if they are not glaringly obvious  - but even  
then, we must look out also for less obvious ones).

So I think if we want to distinguish between the common page or  
page-sample pased approach and something else, this something else  
would be *processes*: a particular sequence of pages, page states and  
user interactions that lead to a definable result. One can focus on  
those, but we should keep in mind that the accessibility of individual  
pages must not be ignored over this. So a problem for any calculation  
of score is how the assessment of processes can be integrated with  
results from page sample checks which in my view won't simply be  
unnecessary - unless you define the use of *any* page alone as a  

Maybe I misunderstood. Can please someone step forward and explain  
what a "problem-centred" approach is supposed to mean and how it can  
ensure that important barriers are not overlooked?


Quoting kvotis@iti.gr:

> Hi to all
> i aggree with Richard and others regarding the problem-centred approach.
> We have followed the same approach in the FP7 ACCESSIBLE project
> assessment tools where the evaluation could be also performed through the
> usage of different categories of personas, functional limitations, etc.
> regards
> kostas
> -------------------
> Dr. Konstantinos Votis
> Computer Engineer & Informatics,PhD, Msc, MBA
> Research Associate
> Informatics and Telematics Institute
> Centre for Research and Technology Hellas
> 6th Klm. Charilaou - Thermi Road
> P.O. BOX 60361 GR - 570 01
> Thessaloniki &#8211; Greece
> Tel.: +30-2311-257722
> Fax : +30-2310-474128
> E-mail : kvotis@iti.gr
>> Hi,
>> I agree with Vivienne and Kerstin that a problem-centred approach is best.
>> Using problems means that you look at the whole website (if appropriate)
>> and
>> are able to identify particular groups that are disadvantaged by the
>> issues
>> found. This is much more useful if you want to compare sites. Explaining
>> that 20% of pages are not accessible has less impact than saying that a
>> particular group (keyboard users,  blind users etc.) cannot use the site.
>> You can still apply the problem-centred approach to single pages,
>> templates
>> or components.
>> Richard
>> -----Original Message-----
>> From: Kerstin Probiesch
>> Sent: Saturday, September 03, 2011 12:08 PM
>> To: 'Eval TF'
>> Cc: 'Vivienne CONWAY'
>> Subject: AW: Additional Point/Question: problem centered / page centered
>> evaluation
>> Hi Vivienne, hi TF,
>>> The question of problem-centered or page-centered approach is going to
>>> be tricky.
>> Yes. It is.
>>> Personally I favour the problem-centered approach as I am
>>> seldom assessing a single page.  Violations in my opinion, usually are
>>> duplicated across pages.  For example if there is a lack of keyboard
>>> access on a single page, that is likely to occur on most if not all
>>> pages.  Some websites are so huge, that a page-centered approach is
>>> simply not feasible.
>> Same opinion. When following a page-centered approach you have to document
>> the same problem on every page again and again. Keyboard access is a good
>> example for that, another one is SC 3.1.1. The more single pages you have,
>> the more the page-centered approach might be imo insufficient. Not only
>> for
>> the accessibility statement/report/result but also for the steps a website
>> owner has to do or order to do. An example: you have a huge website with
>> hundreds or more single pages and - let me say - 10 or more categories. In
>> this case an evaluation guided by a problem-centered approach will find
>> more
>> violations and according to my experiences you can e.g. find out if
>> all/not
>> all/just some/or one online editor/s know how to organize the content (Hx,
>> lists,...) or how to deal with SC 1.1.1. In addition you can give specific
>> instructions.
>> Another problem of the page-centered approach is imo the following: You
>> _have_ to define a set of "typical" pages to test on every website as part
>> of the methodology. A website owner would complain if you test different
>> types. What happens in following situation: on one homepage (main page)
>> you
>> have a video which violates the SC, on another website you also have a
>> video
>> which violates the SC but the video is not on the main page and probably
>> also not on one of the defined set of pages according to the followed
>> page-centered approach? One can argue: in this case we are testing also
>> the
>> video. But, what about 1.3.3, 1.4.1 and 1.3.1 and how to deal with
>> processes? Important questions I think are
>> - are accessible statements which are reliable and valid based upon X
>> (3,4,5,10?) pages possible and how many pages one have to test? This
>> corresponds with "R04: Replicability: different Web accessibility
>> evaluators
>> who perform the same tests on the same site should get the same results
>> within a given tolerance."
>> - how avoid human errors during the process of page selection before
>> starting a particular test and during the test itself?
>> Nevertheless and even if I prefer a problem-centered approach, a
>> page-centered one is probably the only acceptible and pragmatical method
>> when you have to test a great amount of websites in a comparative study -
>> but here again I think we will have limitations with consequences for the
>> accessibility statement(s).
>> I suggest that we also discuss, if we as TF should give redommendations/
>> suggestions for different scenarios:
>> - testing one single page (test should include every SC on this single
>> page)?!
>> - testing a website (walkthrough for every single SC _and_ every single
>> step
>> of a process, if existing)?!
>> - comparative studies (testing every SC on a defined set of "typical"
>> pages)
>> ?!
>> - (...)?!
>> And we also have to consider the conformity levels.
>> I'm thinking about if it might be helpful to collect possible scenarios to
>> see which approach might be the best for a given scenario resp. discuss if
>> we recommend one approach for all scenarios?
>> Last not least: Also the problem-centered approach might lead to problems.
>> In the page-centered approach a tester has finished the test when checked
>> all SCs for the collected single pages. In a problem-centered approach one
>> have to find other criterias otherwise the tester is "lost in violations"
>> depending on the quality of the website.
>>> On the other hand, a developer who is adding a single page and wanting
>>> to know if it meets accessibility criteria would be testing only that
>>> page.  Thoughts?
>> This is an interesting question. It can be that the added single page
>> belongs to an already tested website or not. If the added single belongs
>> to
>> an already tested site, maybe the test is long ago. I think in case of an
>> added single page a test should include all SCs which indicates the
>> problem-centered approach.
>> I hope my points are clear. Sadly, I'm not very familiar in writing
>> English
>> :-( practice will do, hopefully.
>> Regards
>> Kerstin
>>> Regards
>>> Vivienne L. Conway
>>> ________________________________________
>>> From: public-wai-evaltf-request@w3.org [public-wai-evaltf-
>>> request@w3.org] On Behalf Of Shadi Abou-Zahra [shadi@w3.org]
>>> Sent: Tuesday, 30 August 2011 5:05 PM
>>> To: Eval TF
>>> Subject: Fwd: Additional Point/Question: problem centered / page
>>> centered  evaluation
>>> -------- Original Message --------
>>> Subject: Additional Point/Question: problem centered / page centered
>>> evaluation
>>> Date: Tue, 30 Aug 2011 08:21:34 +0000
>>> From: Kerstin Probiesch <mail@barrierefreie-informationskultur.de>
>>> To: <public-wai-evaltf@w3.org>
>>> Dear Eval TF,
>>> I want to add the following question: should we recommend a problem
>>> centered
>>> or a page centered approach? In my opinion this question is not only
>>> essential for further discussions about single questions and topics
>>> (true/false, rankings, involve people with disabilities) but essential
>>> for
>>> the whole methodology.
>>> Regs
>>> Kerstin
>>> -------------------------------------
>>> Kerstin Probiesch - Freie Beraterin
>>> Barrierefreiheit, Social Media, Webkompetenz
>>> Kantstra?e 10/19 | 35039 Marburg
>>> Tel.: 06421 167002
>>> E-Mail: mail@barrierefreie-informationskultur.de
>>> Web: http://www.barrierefreie-informationskultur.de
>>> XING: http://www.xing.com/profile/Kerstin_Probiesch
>>> Twitter: http://twitter.com/kprobiesch
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Received on Monday, 5 September 2011 07:42:01 UTC

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