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Re: Checkpoint 3.4 again

From: Anne Pemberton <apembert@erols.com>
Date: Sat, 28 Jul 2001 20:29:38 -0400
Message-Id: <>
To: "Sean B. Palmer" <sean@mysterylights.com>, "Joe Clark" <joeclark@joeclark.org>, <w3c-wai-gl@w3.org>

         You are right that we do not speak in the same vocabulary. We come 
from diverse segments of the web community, and our vocabulary will be 
diverse. I use the term "web site" to refer to a collection of "web pages" 
which are what you call "HTML documents". If to you, HTML documents are a 
subset of SMGL documents, then you can consider that I may not have as 
broad a definition of "web page" types as you do.

         The rest inline with point of agreement skipped instead of 
inserting "I agree"....

At 11:58 PM 7/28/01 +0100, Sean B. Palmer wrote:
>[Long-ish rant folows, including a new proposal for CP3.2.]
>Hi Anne,
> > No matter the arguments presented, text is an element on a
> > page, no more, and no less. It needs an equivalent. [...]
>This bit of text baffles me (perhaps it needs an equivalent). I
>presume the first sub clause of the sentence is a typo, but I'm still
>baffled as to what you mean by "text is an element on a page". By
>page, I'm presuming you mean document, and by document I'm presuming
>you mean some type of SGML format, (e.g. HTML). Usually, when people
>refer to the term "element" with respect to Web documents, they mean
>the '<img src="a" alt="a"/>' bits. So perhaps it is just my stubborn
>vocabulary that is getting in the way.
I am perhaps expanding the meaning of element to include the most basic 
element on a web page or document, the text ...

>The case that Joe presents is compelling. There are some things that
>are expressible in text that cannot be conveyed by images, and vice
>versa. You can often supplement these media types, but you can't
>really provide equivalents. Even if you have a simple banner with some
>text in it, it is very difficult to get across what that banner looks
>like to people, because you will have to interpret its color, font
>style etc.
Abstract art is more difficult to express in text than detailed photos, but 
even the best detailed description can overlook the mood or sense conveyed 
by details that are hard to describe ... If you put a candid shot of your 
grandmother into your photo editing software, and edit the picture down to 
show the soft pink and white glow of her skin instead of the wonderful 
wrinkles you love in person, how would you describe this picture to your 
friends? Your family? etc?
Even a long description cannot be considered a "true equivalent" in the 
mathematical sense.

>The Pemberton Principle is something that people seem to have missed
>for some time, and something that I for one have been very guilty in
>not following. But when you take "illustrate where this may benefit
>your users" to the extreme, I feel that this damages the case that you
>have built up for it. Perhaps after struggling for so long to get
>people to realise the "illustrations are acceptable for all, useful
>for some, and essential for others" you're trying to subject us to the
>absurdities that we've subjected in the opposite direction for so long
I know, I know, this can lead to all kinds of absurdities, which can cloud 
the issue ... would it be better if the guideline said "if you have the 
elements to do so, provide as much illustration for your text as available" 
... that is rather practical ... but not much of a guideline ...

>I support your (and Joe's) comments that WCAG 2.0 is ambiguous in what
>it says about providing illustrations. It does not phrase it well at
>all, in my humble opinion. It is clear that on some occasions,
>providing images is essential because it puts across concepts that are
>almost impossible to process. A good example is when explaining RDF
>Schemata principles to people using XML RDF code; it's very difficult
>to read. Node and arcs diagrams on the other hand are simpler for most
>people to grok. People who can't see the nodes and arcs diagrams? Once
>the problem of how to gracefully transform SVG is sorted out, it
>should be easy to tab through or otherwise explore diagrams in ways
>which would simply not be possible for bitmapped images.
I grinned thru reading the above .... I've no idea what you are 
illustrating .... my day to day concerns are illustrating the Famous 
Americans my kids are required to learn about  ... at the beginning of the 
summer I tried to finish up stuff I'd started during the school year, and 
made a nifty page for the Kindergarten teachers to use to teach Davy 
Crockett, with his picture (click to see big), background midi music of the 
theme song from an old TV show with the legend of the guy, and the words to 
the song for the teacher to teach to the kids to learn the basic legend of 
ole Davy. It's at 
http://www.geocities.com/apembert45/history/DavyCrockett.html   .... (if it 
doesn't work, let me know)
Funny end of the story is that I did that page in June, and in July the 
state issued new curriculum standards and Davy Crockett is off the lists 
..... arggggghhhhhhh!

>So to WCAG 2.0: as with all guidelines/techniques documents, the
>layout is bound to be inherently flawed due to the fact that it
>interprets and then displays the concepts that we are trying to
>express: a hierarchy instead of a Web. We also know that certain forms
>of hierarchy are more effective than others, although the exact
>details of the relationships are subjective. Let's not quibble over
>this waste of time, and instead concentrate on what we really want to
>get people to do.

Sean, one of the benefits of the web is that the hierarchy is open to the 
user .... Do you want to read the whole article first, or click on the 
links as you go thru the first time .... it's your option. Whatever 
"research" tells you about "effectiveness" is applicable to some people, 
and not to others .... it's an average, and what accessibility needs to 
address are the extremes ........

>We want people to illustrate text, if they have the tools to do so,
>where this would benefit the user. We must realise that sometimes,
>providing illustrations is difficult, in much the same way that we
>must realise that writing clearly is not easy for some people. I don't
>consider myself to be a clear writer, and especially when compared to
>the likes of William or Wendy, my writing style could be considered
>terrible. We can't force people to compensate for things that are out
>of control. To do so would be an incredible absurdity.
That's why I don't like the current 3.4 saying that illustrations have to 
do "thus and so" .... First put the illustrations there ... then  consider 
how to use them best .... "main concepts and relationships" may not be the 
illustration that is available ...

>What do we hope to achieve by the document stating these facts?
>Really? I think that we want people to mull over the fact they, hey,
>maybe they aren't illustrating their documents enough. We can't force
>them to illustrate. It's even difficult to evaluate the quality of
>illustrations. All we can do is give people the idea, and hope that it
>has an effect (discernible, or non-discernible) in the way people do
Sean, Maybe I've been hardened by the many "accessibility" pages that were 
proudly devoid of illustrations .... This suggests to me that we need 
strong wording to move the tide ....

>It didn't really come home to me until William was sitting next to me,
>and I presented my homepage to him with the comment "note that it has
>no images". He simply replied, "oh, you have to illustrate it though"
>or somesuch. Bang! Like the koan finally being resolved that it was,
>the mystery of the Pemberton Principle came through. I believe that Al
>did the same thing to William. I'm not sure how Al came across it.
Thanks, Sean, for this window into the Face to Face meetings! I truly wish 
I was able to participate, but as William told someone recently, travel is 
funded by whomever you get to pay for it .... mostly you .... and if I had 
travel money, I would be visiting my Mom in a nursing home half a continent 
away ... Plus, I've never had a passport - no reason to need it! But if 
wishes could come true, I'd love to come to one or a few Face to Faces, and 
meet some of you.  Al was an "early convert" to the idea of graphics as an 
equivalent of text, which led to the notion of universal equivalency ...

>We want to somehow reproduce this in WCAG 2.0. Trouble is, we can't
>all have William sitting next to us when we're designing sites :-)
>We don't want people to say "that's absurd" (illustrate everything),
>and we don't want them to say "duh" (illustrate something). We want
>them to realise the importance of illustrations. Here, then (after all
>of this waffle) is my proposal:-
>Checkpoint: 3.4 Utilise content in a wide range of modalities where
>possible to assist the users of your content.
>Explanation: Where tools permit and cases warrant, provide, for
>example, illustrations for text that may enable people to pick up on
>concepts that would previously be difficult to comprehend.
>Rationale: Pointing out concepts, or augmenting current ones using
>illustrations or other media is acceptable to all users, may be
>helpful to many, and under some circumstances may be imperative for

Sean, I would invert the order of the users in the Rationale, listing those 
it as imperative first, helpful to many next, and acceptable to all last 
... Otherwise, it's a great wording of what the guideline is supposed to be 

>(more specific examples can follow).
>I think that gets across in a sensible and realistic manner the
>concept that we are trying to impart to people with this checkpoint.
>It's short, and to the point.
>And please, please, please, get rid rid of the non-normative example:
>it's absolutely rediculous. The phrase "a text equivalent equals its
>non-text equivalent" is theoretically correct (all eqiuvalents are
>equal!) but practically, it's mind boggling. Perhaps people have a
>much looser definition of "equivalent" than I do. When something is
>equivalent to another, in the mathematical sense, they can be
>substituted without changing anything that the formula is expressing.
>If text were equivalent to images in any way, we're be able to use
>them totally interchangable without any side effects. This is clearly
>not the case (else we wouldn't be having this discussion, and the
>checkpoint would have no meaning!), so although the formula "a text
>equivalent equals its non-text equivalent" is logically sound, there
>can be no instances to justify it.

Sorry, Sean, I'm not much of a mathematical person when it comes to 
definitions. Equivalency has a broader meaning to me ... in the 
mathematical sense neither alt tags nor long description are equivalencies, 
tho perhaps the scripts of multi-media is close ...


Anne Pemberton

Received on Saturday, 28 July 2001 20:37:04 UTC

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