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Re: Proper way to markup citations and detailed image alttext?

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From: Cliff Tyllick
Date: Jan 16, 2009 9:35AM

On Thu, Jan 15, 2009 at 2:05 PM, Dean Hamack < <EMAIL REMOVED> > wrote:
And let's say you have a pie chart which shows percentages of something. I can easily create text that says "x=20%, y=50%, etc." but it seems like it might be a little long for an alt tag.
Chris Hoffman < <EMAIL REMOVED> > replied:

Why not have an accompanying paragraph that describes the data in the chart? It would be useful to all users, would fulfill the requirement of alternative text, and would make the contents of the chart indexable by search engines.

Cliff adds:

Dean, I realize that your pie chart is probably a theoretical example, but before you decide a pie chart is the best visual presentation of the data, you might check out any one of Edward Tufte's fine books at http://www.edwardtufte.com/tufte/books_vdqi. Among them, The Visual Display of Quantitative Information is likely to come closest to hitting the mark. His forum, http://www.edwardtufte.com/bboard/q-and-a?topic_id=1, is a great place to read expansions on this approach and includes at least one thread on pie charts: http://www.edwardtufte.com/bboard/q-and-a-fetch-msg?msg_id=00018S&;topic_id=1&topic=Ask+E.T.

I mention this because so often the most significant barrier to accessibility is that the content is not usable in the first place, and so often the most significant barrier to usability is a failure to communicate clearly. The most accessible Web pages work well at all three levels.

Cliff Tyllick
Web development coordinator
Agency Communications Division
Texas Commission on Environmental Quality
512-239-4516
<EMAIL REMOVED>