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Re: AW: EvalTF discussion 5.5 and actual evaluation

From: Alistair Garrison <alistair.j.garrison@gmail.com>
Date: Mon, 16 Jan 2012 10:37:48 +0100
To: Kerstin Probiesch <k.probiesch@googlemail.com>, Eval TF <public-wai-evaltf@w3.org>
Message-Id: <E5B166CA-0A8C-460F-A903-D917D783CDBC@gmail.com>
Hi Kerstin, Eval TF,

We have no choice but to use the testing procedures defined in individual techniques, when those techniques have been implemented.

Referencing http://www.w3.org/TR/WCAG-TECHS/intro.html...

In the section "Sufficient and Advisory Techniques"  - you will note, that sufficient techniques exist for each Success Criterion that, if implemented correctly, are 'sufficient' to meet that Success Criterion.

It is true that we cannot say using just these sufficient techniques is the only way to meet success criteria - as a developer can show (how???) that they have met a success criteria by using their own techniques (also presents a problem for testing as the tester (or someone) would then have to assume responsibility for saying these new techniques are sufficient)...  

And, as I mentioned in my previous email there are some occasions where two or more techniques are provided for doing the same thing.  In this case if we were to test both (as both are relevant), one might fail and one might pass, if we only look at the passes and fails we would make the wrong judgment for the success criteria - as only the implemented technique should have been assessed.   

This is presumably why the Testing Techniques section of this document contains the sentence "In particular, test procedures for individual techniques should not be taken as test procedures for the WCAG 2.0 success criteria overall." - although, it might have been amended to "test procedures for all relevant individual techniques" for clarity.   Especially, as the paragraph runs on:

"While the test procedure for a given technique may produce a fail result, because the technique was not used, the success criterion may be met via another technique. It is even possible that the success criterion is met via a technique that is not documented in this collection, so failing test procedures for all documented sufficient techniques may not mean that the success criterion is not met."

However, if you concentrate solely on testing actually implemented sufficient techniques (which due to reduced overheads I assume will be used by the majority of people) the summation of their pass / fail / non-applicable results will, by design, be 'sufficient' to state if a success criteria is passed / failed / non-applicable.

You have most certainly raised several interesting questions...  Should we concern ourselves with assessing only implemented sufficient techniques, or should we take on the wider responsibility of verifying / assessing people's custom techniques?  If we only concentrate on implemented sufficient techniques - will the W3C provide a mechanism for people to submit custom techniques, for verification, which they believe also fulfil success criteria?

Very best regards 

Alistair 

On 16 Jan 2012, at 09:11, Kerstin Probiesch wrote:

> Hi Alistair, all,
> 
> I think we should be very careful with any testing procedures which rely on
> techniques. Techniques are mainly for developers/authors. In the Techniques
> Document we find:
> 
> "Test procedures are provided in techniques to help verify that the
> technique has been properly implemented."
> 
> And:
> 
> "In particular, test procedures for individual techniques should not be
> taken as test procedures for the WCAG 2.0 success criteria overall."
> 
> Best
> 
> Kerstin
> 
> 
> 
>> -----Ursprüngliche Nachricht-----
>> Von: Alistair Garrison [mailto:alistair.j.garrison@gmail.com]
>> Gesendet: Samstag, 14. Januar 2012 14:45
>> An: Eval TF
>> Betreff: Re: EvalTF discussion 5.5 and actual evaluation
>> 
>> Dear All,
>> 
>> To my mind there are no massively different ways to evaluate the WCAG
>> 2.0 guidelines - seemingly, intentionally so.  We also don't need to
>> take one of the WCAG 2.0 checkpoints and determine a way to assess it -
>> as this has already been done for us.
>> 
>> From WCAG 2.0 it seems reasonably clear that you (in some way)
>> determine which techniques are applicable to the content in the pages
>> you want to assess, then you simply follow the Test Procedures
>> prescribed in each of the applicable techniques. It does not matter if
>> you do this one by one, per theme, per technology etc... that is surely
>> up to whatever you think is best at the time.
>> 
>> Again, I'm a little concerned that we might be wandering towards
>> recreating test procedures for individual techniques, when as mentioned
>> that part has already been done by the WCAG 2.0 techniques working
>> group. Isn't it the higher level question of how to approach the
>> evaluation of a website (or conformance claim), and capture results, in
>> a systematic way that we need to be answering?
>> 
>> For example, an approach such as...
>> 
>> 1) Clearly define what you want to test - the WCAG 2.0 Conformance
>> Claim (or in its absence our website scoping method)...
>> 2) Determine which techniques are applicable - by looking through these
>> pages and finding relevant content, marking techniques non-applicable
>> if no applicable content can be found.
>> 3) Running all relevant test procedures (defined in applicable
>> techniques) against all applicable content (found in 2).
>> 4) Finally recording pass, fail or non-applicable for each relevant
>> technique, and then determining from this all passed, failed and non-
>> applicable checkpoints / guidelines.  Noting that there are several
>> techniques available for doing certain things.  (Note: this is another
>> reason why we might use the Conformance claim as techniques which have
>> been used will hopefully be recorded, rather than us having to assess
>> all techniques for a certain thing, until one is passed).
>> 
>> Just my thoughts...
>> 
>> Very best regards
>> 
>> Alistair
>> 
>> On 14 Jan 2012, at 05:38, Vivienne CONWAY wrote:
>> 
>>> HI Richard and all TF
>>> While I understand the need to look at the procedures from an overall
>> perspective first, I agree with Richard that it may be time to try out
>> a few idea for practical implementation.  It may be a good idea for us
>> all to take one of the WCAG 2.0 checkpoints and determine a way to
>> assess it.  However, I remember (think it might have been Detlev)
>> proposed that we do this and it was decided that we wouldn't be dealing
>> with each point individually.  Or did I misunderstand?
>>> 
>>> 
>>> Regards
>>> 
>>> Vivienne L. Conway, B.IT(Hons)
>>> PhD Candidate & Sessional Lecturer, Edith Cowan University, Perth,
>> W.A.
>>> Director, Web Key IT Pty Ltd.
>>> v.conway@ecu.edu.au<mailto:v.conway@ecu.edu.au>
>>> v.conway@webkeyit.com<mailto:v.conway@webkeyit.com>
>>> Mob: 0415 383 673
>>> 
>>> This email is confidential and intended only for the use of the
>> individual or entity named above. If you are not the intended
>> recipient, you are notified that any dissemination, distribution or
>> copying of this email is strictly prohibited. If you have received this
>> email in error, please notify me immediately by return email or
>> telephone and destroy the original message.
>>> 
>>> ________________________________
>>> From: RichardWarren [richard.warren@userite.com]
>>> Sent: Saturday, 14 January 2012 10:32 AM
>>> To: Eval TF
>>> Subject: Re: EvalTF discussion 5.5 and actual evaluation
>>> 
>>> Dear TF,
>>> 
>>> I cannot help thinking that we would save a lot of time and
>> discussion if we concentrated on procedures for evaluation (5.3) where
>> we are going to try “ to propose different ways to evaluate the
>> guidelines: one by one, per theme, per technology, etc” .  As we do
>> that we will come across the various technologies (5.2) and possibly
>> come up with a few acceptable ways of dealing with “occasional errors”
>> etc. if and when relevant to a particular guideline. This approach may
>> be more efficient than trying to define systemic and incidental errors
>> in a non-specific guideline context.
>>> 
>>> I wonder if now is the time to get to the core of our task and start
>> working on actual procedures where we can discuss levels of compliance
>> and any effect in a more narrow, targeted environment.
>>> 
>>> Regards
>>> Richard
>>> 
>>> 
>>> From: Elle<mailto:nethermind@gmail.com>
>>> Sent: Friday, January 13, 2012 11:35 PM
>>> To: Vivienne CONWAY<mailto:v.conway@ecu.edu.au>
>>> Cc: Alistair Garrison<mailto:alistair.j.garrison@gmail.com> ; Shadi
>> Abou-Zahra<mailto:shadi@w3.org> ; Eval TF<mailto:public-wai-
>> evaltf@w3.org> ; Eric Velleman<mailto:evelleman@bartimeus.nl>
>>> Subject: Re: EvalTF discussion 5.5
>>> 
>>> TF:
>>> 
>>> I have been reading the email discussions with avid interest and very
>> little ability to add anything valuable yet.  My point of view seems to
>> be very different from most in the group, as my job is to meet and
>> maintain this conformance at a large organization. I'm learning quite a
>> bit from all of you.
>>> 
>>> I've been following this particular topic with a keen interest in
>> seeing what a "margin of error" would be defined as, in part because
>> our company is about to launch into a major site consolidation and I'm
>> curious about how to scale our current testing process.  Until now,
>> we've actually been testing every page we can with both automated scans
>> and manual audits.
>>> 
>>>> From a purely layman's point of view, the only confidence I have
>> when testing medium to large volume websites (greater than 500 pages)
>> is by doing the following:
>>> 
>>> 1. automated scans of every single page
>>> 2. manual accessibility testing modeled after the user acceptance
>> test cases to test the critical user paths as defined by the business
>>> 3. manual accessibility testing of each page type and/or widget or
>> component (templates, in other words)
>>> 
>>> So, I felt the need to chime in on "margin of error," because it
>> worries me when we start quantifying a percentage of error. I see this
>> from the corporate side.  Putting a percentage on this may actually
>> undermine the overall success of accessibility specialists working
>> inside of a large organization.  We may find ourselves with more
>> technical compliance and less overall usability for disabled users. As
>> for me, I need to be able to point to an evaluation technique that
>> encompasses more than a codified measurement in my assessment of a
>> website's conformance.  Ideally, the  really needs to account for user
>> experience.  It's one of the fail safes in the current 508 Compliance
>> requirements that I've taken shelter in, actually, as outdated as they
>> are - functional performance criteria.
>>> 
>>> I really appreciate the work everyone in this group is doing, as I
>> will likely be a direct recipient of the outcome as I put these
>> concepts into action over the course of their creation.  Consider me
>> the intern who will try to see if these dogs will hunt. :)
>>> 
>>> 
>>> Much appreciated,
>>> Elle
>>> 
>>> 
>>> On Thu, Jan 12, 2012 at 8:10 PM, Vivienne CONWAY
>> <v.conway@ecu.edu.au<mailto:v.conway@ecu.edu.au>> wrote:
>>> Hi Alistair and TF
>>> You have raised an interesting point here.  I'm thinking I like your
>> idea better than the 'margin of error' concept.  It removes the
>> obstacle of trying to decide what constitutes an 'incidental' or
>> 'systemic' error.  I thnk it's obvious that most of the time a website
>> with systemic errors would not pass, unless it was sytem-wide and
>> didn't pose any serious problem ie.a colour contrast that's .1 off the
>> 4.5:1 rule.  I think I like the statement idea coupled with a
>> comprehensive scope statement of what was tested.
>>> 
>>> 
>>> Regards
>>> 
>>> Vivienne L. Conway, B.IT<http://B.IT>(Hons)
>>> PhD Candidate & Sessional Lecturer, Edith Cowan University, Perth,
>> W.A.
>>> Director, Web Key IT Pty Ltd.
>>> v.conway@ecu.edu.au<mailto:v.conway@ecu.edu.au>
>>> v.conway@webkeyit.com<mailto:v.conway@webkeyit.com>
>>> Mob: 0415 383 673
>>> 
>>> This email is confidential and intended only for the use of the
>> individual or entity named above. If you are not the intended
>> recipient, you are notified that any dissemination, distribution or
>> copying of this email is strictly prohibited. If you have received this
>> email in error, please notify me immediately by return email or
>> telephone and destroy the original message.
>>> ________________________________________
>>> From: Alistair Garrison
>> [alistair.j.garrison@gmail.com<mailto:alistair.j.garrison@gmail.com>]
>>> Sent: Thursday, 12 January 2012 6:41 PM
>>> To: Shadi Abou-Zahra; Eval TF; Eric Velleman
>>> Subject: Re: EvalTF discussion 5.5
>>> 
>>> Hi,
>>> 
>>> The issue of "margin of error" relates to the size of the website and
>> the number of pages actually being assessed.  I'm not so keen on the
>> "5% incidental error" idea.
>>> 
>>> If you assess 1 page from a 1 page website there should be no margin
>> of error.
>>> If you assess 10 pages from a 10 page website there should be no
>> margin of error.
>>> If you assess 10 pages from a 100 page website you will have
>> certainty for 10 pages and uncertainty for 90.
>>> 
>>> Instead of exploring the statistical complexities involved in trying
>> to accurately define how uncertain we are (which could take a great
>> deal of precious time) - could we not just introduce a simple
>> disclaimer e.g.
>>> 
>>> "The evaluator has tried their hardest to minimise the margin for
>> error by actively looking for all content relevant to each technique
>> being assessed which might have caused a fail."
>>> 
>>> Food for thought...
>>> 
>>> Alistair
>>> 
>>> On 12 Jan 2012, at 10:04, Shadi Abou-Zahra wrote:
>>> 
>>>> Hi Martijn, All,
>>>> 
>>>> Good points but it sounds like we are speaking more of impact of
>> errors rather than of the incidental vs systemic aspects of them.
>> Intuitively one could say that an error that causes a barrier to
>> completing a task on the web page needs to be weighted more
>> significantly than an error that does not have the same impact, but it
>> will be difficult to define what a "task" is. Maybe listing specific
>> situations as you did is the way to go but I think we should not mix
>> the two aspects together.
>>>> 
>>>> Best,
>>>> Shadi
>>>> 
>>>> 
>>>> On 12.1.2012 09:41, Martijn Houtepen wrote:
>>>>> Hi Eric, TF
>>>>> 
>>>>> I would like to make a small expansion to your list, as follows:
>>>>> 
>>>>> Errors can be incidental unless:
>>>>> 
>>>>> a) it is a navigation element
>>>>> b) the alt-attribute is necessary for the understanding of the
>> information / interaction / essential to a key scenario or complete
>> path
>>>>> c) other impact related thoughts?
>>>>> d) there is an alternative
>>>>> 
>>>>> So an unlabeled (but required) field in a form (part of some key
>> scenario) will be a systemic error.
>>>>> 
>>>>> Martijn
>>>>> 
>>>>> -----Oorspronkelijk bericht-----
>>>>> Van: Velleman, Eric
>> [mailto:evelleman@bartimeus.nl<mailto:evelleman@bartimeus.nl>]
>>>>> Verzonden: woensdag 11 januari 2012 15:01
>>>>> Aan: Boland Jr, Frederick E.
>>>>> CC: Eval TF
>>>>> Onderwerp: RE: EvalTF discussion 5.5
>>>>> 
>>>>> Hi Frederick,
>>>>> 
>>>>> Yes agree, but I think we can have both discussions at the same
>> time. So:
>>>>> 1. How do we define an error margin to cover non-structuraal
>> errors?
>>>>> 2. How can an evaluator determine the impact of an error?
>>>>> 
>>>>> I could imagine we make a distinction between structural and
>> incidental errors. The 1 failed alt-attribute out of 100 correct ones
>> would be incidental... unless (and there comes the impact):
>>>>> a) it is a navigation element
>>>>> b) the alt-attribute is necessary for the understanding of the
>> information / interaction
>>>>> c) other impact related thoughts?
>>>>> d) there is an alternative
>>>>> 
>>>>> We could set the acceptance rate for incidental errors. Example:
>> the site would be totally conformant, but with statement that for alt-
>> attributes, there are 5% incidental fails.
>>>>> This also directly relates to conformance in WCAG2.0 specifically
>> section 5 Non-interference.
>>>>> 
>>>>> Eric
>>>>> 
>>>>> 
>>>>> 
>>>>> ________________________________________
>>>>> Van: Boland Jr, Frederick E.
>> [frederick.boland@nist.gov<mailto:frederick.boland@nist.gov>]
>>>>> Verzonden: woensdag 11 januari 2012 14:32
>>>>> Aan: Velleman, Eric
>>>>> CC: Eval TF
>>>>> Onderwerp: RE: EvalTF discussion 5.5
>>>>> 
>>>>> As a preamble to this discussion, I think we need to define more
>> precisely ("measure"?) what an "impact" would be (for example, impact
>> to whom/what and what specifically are the consequences of said
>> impact)?
>>>>> 
>>>>> Thanks Tim
>>>>> 
>>>>> -----Original Message-----
>>>>> From: Velleman, Eric
>> [mailto:evelleman@bartimeus.nl<mailto:evelleman@bartimeus.nl>]
>>>>> Sent: Wednesday, January 11, 2012 4:15 AM
>>>>> To: public-wai-evaltf@w3.org<mailto:public-wai-evaltf@w3.org>
>>>>> Subject: EvalTF discussion 5.5
>>>>> 
>>>>> Dear all,
>>>>> 
>>>>> I would very much like to discuss section 5.5 about Error Margin.
>>>>> 
>>>>> If one out of 1 million images on a website fails the alt-attribute
>> this could mean that the complete websites scores a fail even if the
>> "impact" would be very low. How do we define an error margin to cover
>> these non-structural errors that have a low impact. This is already
>> partly covered inside WCAG 2.0. But input and discussion would be
>> great.
>>>>> 
>>>>> Please share your thoughts.
>>>>> Kindest regards,
>>>>> 
>>>>> Eric
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>> 
>>>> --
>>>> Shadi Abou-Zahra - 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)
>>>> 
>>> 
>>> This e-mail is confidential. If you are not the intended recipient
>> you must not disclose or use the information contained within. If you
>> have received it in error please return it to the sender via reply e-
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>> contained within is not the opinion of Edith Cowan University in
>> general and the University accepts no liability for the accuracy of the
>> information provided.
>>> 
>>> CRICOS IPC 00279B
>>> 
>>> 
>>> 
>>> 
>>> --
>>> If you want to build a ship, don't drum up the people to gather wood,
>> divide the work, and give orders. Instead, teach them to yearn for the
>> vast and endless sea.
>>> - Antoine De Saint-Exupéry, The Little Prince
>>> 
>>> 
>>> ________________________________
>>> This e-mail is confidential. If you are not the intended recipient
>> you must not disclose or use the information contained within. If you
>> have received it in error please return it to the sender via reply e-
>> mail and delete any record of it from your system. The information
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> 
> 
Received on Monday, 16 January 2012 09:38:49 GMT

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