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RE: All pages

From: Kathleen Wahlbin <kathy@interactiveaccessibility.com>
Date: Tue, 26 Jun 2012 08:38:50 -0400
To: "'Shadi Abou-Zahra'" <shadi@w3.org>, "'Alistair Garrison'" <alistair.j.garrison@gmail.com>
Cc: "'Eval TF'" <public-wai-evaltf@w3.org>
Message-ID: <00a001cd5398$a498e3b0$edcaab10$@interactiveaccessibility.com>
Hi -


During our conversations early on, we talked about using a sampling method
to review a set of pages on the site and then automated tools to check the
full site.  Is the recommendation now to check all pages manually?  


If we are suggesting checking all pages manually, then I think we need to be
careful about what this means for different types of websites/web
applications.   Here are two situations (and I am sure there are many more
that we could come up with):


-        For applications, a page could have many different variations
depending on the data or options selected.  Do all of these different
variations need to be checked?


-        For database driven websites, there may be a lot of different pages
but they may all use the same template and the data or content of the page
may be same.  In this case, if the content is added to the page in the same
way, then an evaluator should be able to test just one of these pages rather
than the full set.




 -----Original Message-----
From: Shadi Abou-Zahra [mailto:shadi@w3.org] 
Sent: Tuesday, June 26, 2012 6:21 AM
To: Alistair Garrison
Cc: Eval TF
Subject: Re: All pages


Hi Alistair,


I'm not sure what you mean by overkill. Maybe it is not economically
feasible to check all pages but ideally all pages are checked before making
an accessibility statement about them (especially for small websites where
the use of templates, content management systems, and other quality
assurance procedures are often less sophisticated).


We should bear in mind that no matter how robust a sampling method is, there
is always a possibility that an evaluator misses critical parts of the
website through sampling. Sampling is always an approximation but ideally it
is "close enough" to reality except for few edge cases.


What is the problem with saying something like "if you can check all the
pages then please go ahead and ignore the sampling section"?


Sidenote: A production line already assumes large amounts of products that
are produced in the same way, so that sampling becomes effective for quality
assurance. However, not all websites are developed this way, and most
websites actually resemble a handicraft store... ;)






On 26.6.2012 11:56, Alistair Garrison wrote:

> Hi Shadi, Richard,


> Re-reading your emails you seem to be looking at conformance evaluation
from a new viewpoint (maybe rightly / maybe wrongly?) from the one we seem
to have adopted to date.


> Viewpoint 1 (to date) is an evaluator wishing to see if a whole website
conforms with WCAG 2.0.


> With regard to this viewpoint an evaluator doesn't need to check all
pages, simply enough to confirm whether the website conforms or doesn't.  If
there are several examples of content which pass a checkpoint and the same
team has built all the site, I suppose you can assume that the other
relevant instances of content will also be ok, and visa versa for content
with issues.  You would not think about checking all items on a production
line, would you?

> Historically most people seem to think this type of evaluation is
efficiently and effectively achieved by sampling, which is reflected in
their different methodologies.  Checking all pages could be seen as
unnecessary 'overkill' even on small sites...


> Viewpoint 2 (new) is a website owner wanting to find and correct all
faults in their website - in which case they would want to look at all pages
no matter what the size.


> Either way, treating the concept as editorial only sounds to me a bit
casual, but I'd be interested to hear other views...


> All the best


> Alistair


> On 26 Jun 2012, at 11:12, Shadi Abou-Zahra wrote:


>> I agree with this approach too. The default (and ideal) would be to check
all pages. In cases where this is not practically feasible we provide a
robust sampling procedure.


>> This probably affects several sections, including the introduction,
though rather editorially only.


>> Regards,

>>   Shadi



>> On 25.6.2012 19:47, RichardWarren wrote:

>>> Michael,

>>> We are not suggesting "all or nothing" .

>>> We are saying that the preferred method is to validate all pages, 

>>> but if this is too large a task (which for typically large sites it 

>>> will be) then here is a sampling procedure which will ensure that 

>>> all important elements are covered.


>>> Thus owners of small sites that want to check their compliance can 

>>> skip the sampling process and get straight on with the method of 

>>> validating their site.


>>> Richard


>>> -----Original Message----- From: Michael S Elledge

>>> Sent: Monday, June 25, 2012 3:34 PM

>>> To:  <mailto:public-wai-evaltf@w3.org> public-wai-evaltf@w3.org

>>> Cc: Alistair Garrison ; RichardWarren ; Eval TF

>>> Subject: Re: All pages


>>> Hi All--


>>> I agree with Alistair. We nearly always test a sample of pages in a 

>>> website. Although it would be ideal to test every page in a site, it 

>>> is impractical because of time and cost, especially if it is 

>>> performed manually. Many people reading our methodology will be 

>>> looking to apply it to their reviews, which out of necessity will be
based on sampling.

>>> The alternative, relying solely on automated checkers to review a 

>>> medium to large site in its entirety, I think we can all agree is 

>>> not a viable alternative, even with their improvements.


>>> We spent a significant amount of time describing sampling approaches 

>>> early in this process, so I'm surprised that the "all or nothing"

>>> approach is still being debated. I may have missed something along 

>>> the way, however, so please forgive me if I did.


>>> Best regards,


>>> Mike


>>> On 6/25/2012 3:08 AM, Alistair Garrison wrote:

>>>> Hi Richard,


>>>> Reading the archive I see we have talked around the subject of 

>>>> sampling - but not actually whether to evaluate all pages instead 

>>>> of a sample. Reading a number of emails, however, it becomes clear 

>>>> that we all seem to use some kind of sampling effort - hence its 

>>>> seemingly automatic acceptance to this point.


>>>> To my mind, there are many reasons for adopting our reasonably 

>>>> straight-forward sample-based approach (again we have all mostly 

>>>> done something similar for years), even for smaller sites, over 

>>>> evaluating all pages.  I suppose its lower cost in terms of time / 

>>>> effort - with the same actual benefits is one of the top reasons for


>>>> I'm also worried that the changes you suggest (did it also need a 

>>>> change to the Requirements docs) at this stage will create a 

>>>> two-tier (all or sample) approach, forking our current work and 

>>>> possibly opening a big can of worms (like how do you realistically, 

>>>> and with very high confidence, find all pages in a website, what 

>>>> exactly is a small or medium site, etc...).


>>>> I remain to be convinced, but I would be interested to hear the 

>>>> views of others.


>>>> All the best


>>>> Alistair


>>>> On 22 Jun 2012, at 12:05, RichardWarren wrote:


>>>>> Reason for making the default position to include all pages 

>>>>> (entire

>>>>> website)


>>>>> 1) Taking the Internet (WWW) as a whole, the majority of sites are 

>>>>> quite small (100 or so pages), typically things like "Mum&  Pop"

>>>>> stores, SME profiles, personal or project websites.


>>>>> 2) Where this is practical a full evaluation is more reliable than 

>>>>> a sample.


>>>>> 3) Our brief is to deliver an evaluation methodology, not a 

>>>>> sampling methodology.


>>>>> 4) Reliable sampling is a complex procedure, if owners of 

>>>>> small/medium sites think they have to go through sampling they 

>>>>> will give up.


>>>>> 5) Sampling procedure will only be required for large sites so it 

>>>>> should be an option. The default should be to evaluate the whole 

>>>>> site. If the evaluator feels that is too large a task then s/he 

>>>>> should have the option to use a sampling procedure to help manage 

>>>>> the evaluation work load.


>>>>> My feeling as that we need to change the order of our text so that 

>>>>> sampling is offered as the option, not the full audit.


>>>>> Richard


>>>>> -----Original Message----- From: Alistair Garrison

>>>>> Sent: Friday, June 22, 2012 10:39 AM

>>>>> To: RichardWarren ; Eval TF

>>>>> Subject: All pages


>>>>> Hi Richard,


>>>>> We were not able to debate the agenda item relating to "testing 

>>>>> all pages"? Can you just remind me what was behind this issue?


>>>>> All the best


>>>>> Alistair






>> --

>> Shadi Abou-Zahra -  <http://www.w3.org/People/shadi/>
http://www.w3.org/People/shadi/ Activity Lead, 

>> W3C/WAI International Program Office Evaluation and Repair Tools 

>> Working Group (ERT WG) Research and Development Working Group (RDWG)








Shadi Abou-Zahra -  <http://www.w3.org/People/shadi/>
http://www.w3.org/People/shadi/ Activity Lead, W3C/WAI International Program
Office Evaluation and Repair Tools Working Group (ERT WG) Research and
Development Working Group (RDWG)



Received on Tuesday, 26 June 2012 12:39:25 UTC

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