- From: Jason White <jasonw@ariel.ucs.unimelb.edu.au>
- Date: Fri, 5 May 2000 09:09:39 +1000 (EST)
- To: Web Content Accessibility Guidelines <w3c-wai-gl@w3.org>
Perhaps Ian's requirement could be reformulated as follows: In order for a web site to be considered accessible, all of its content must be available in a format that complies with the guidelines. This does not preclude the availability of other formats which may be selected by the user, either through explicit action or by content negotiation in pursuance of user-specified preferences. Stated differently, provided that the structure and semantics of the content are available in appropriate markup, equivalents are provided as mandated by the guidelines, device independence is ensured, etc., in one version of the content, this will suffice to satisfy the conformance requirement. One difficulty attendant upon this approach, however, is to define exactly what is meant by "the same" content, for purposes of ensuring compliance. For instance, if the author of a complex sociological monograph were to provide two versions: (1) a highly mathematical version, containing detailed treatment of the relevant statistical parameters and the findings of the study, supplied in a highly presentational file format that can not be rendered effectively in non-visual media; and (2) a simplified exposition of the findings of the study, intended for a general (non-specialist) audience, and in a standard, highly accessible markup language, we would not consider them to be equivalent in the relevant sense, and hence the site as a whole should be regarded as non-compliant. Stated differently, the differences in markup technique (in the file format used), between the two versions, would characterise one as being more accessible than the other, but would not, of itself, lead to the conclusion that they were "different content" for purposes of conformance. However, the simplification of one version, by contrast with the mathematical detail provided in the other, would justify the view that the two versions were not, relevantly, the same, and hence that the site was inaccessible, as there was no accessible version available of the mathematically sophisticated edition of the study. Suppose, on the other hand, that the detailed mathematics were included in both editions, but that the version marked up in a presentational file format made extensive use of graphs and charts that were not reproduced in what the author might regard as the "accessible" edition. Suppose further that, in the latter version, the graphs were replaced by tables purporting to convey the same information. Again, the question arises of whether the two versions have "equivalent" content for conformance purposes. I am concerned that in allowing site-wide compliance on the basis that Ian has suggested, a move which has considerable merit, we need to be careful in defining what is, and what is not, "the same" content, or amounts to two versions of "the same" content, for purposes of judging conformance. Disclaimer: the above are personal comments and have not been made in my capacity as co-chair.
Received on Thursday, 4 May 2000 19:10:25 UTC