- From: Gregg Vanderheiden <gv@trace.wisc.edu>
- Date: Fri, 4 Jun 2004 08:58:07 -0500
- To: <w3c-wai-gl@w3.org>
- Message-ID: <auto-000057426353@spamarrest.com>
Sorry John Let me put it this way. We say that authors must separate information and structure from presentation If structure is information then that is kind of like saying women and people. See my problem? Gregg PS very interesting discourse below. _____ From: John M Slatin [mailto:john_slatin@austin.utexas.edu] Sent: Friday, June 04, 2004 8:26 AM To: Gregg Vanderheiden Subject: RE: 506 definition of structure Gregg asks: "If text is structure what is information?" John responds: It depends (what did you think I'd say? <grin>) And it depends in part on what level of abstraction you're talking about. What humans perceive as "information" doesn't exist in the abstract: it is embodied in some form, some medium. Information may exist in the form of text; it may exist in the form of graphics; it may be embodied in a mathetmatical equation, a chemical formula, an animation generated by a simulation, a video, etc. If a given human already knows the material in question, she or he doesn't perceive it as information, though it may count as information to the person sitting at the next desk. Information *has* structure, and structure is information. In our context, the markup that create structure is information about the shape of the information that a given document makes available. Gregory Bateson says information is news of difference that makes a difference. From this standpoint, a chameleon is always trying *not* to become information-- it wants (biologically speaking) to be indistinguishable from surrounding context. If the context changes faster than the chameleon's skin can respond, it becomes information, and instantly vulnerable to predators to whom the difference makes a difference. The self-organizing behavior of complex adaptive systems (like humans or the Web) depends on a given system's ability to convert what information theory would call "noise" (meaningless stuff coming in from outside) into information *about the system itself*; the system then uses that information to reorganize itself at a higher level of complexity. The Web was exactly such a phenomenon to the whole IT industry, and new technologies for producing and rendering Web content force the same kinds of reorganization-- hence our current effort to rewrite the accessibility guidelines at a higher level of complexity that takes account of all the technologies that are now used to produce Web content. Our guidelines will beomce another rock in the pond, etc, etc. But the proposed definition doesn't say "text *is* structure." It says that text is one of the types of material that may be included in a Web resource. As far as I know, though, for all Web resources that have source documents that employ markup languages (HTML, XML, SVG, etc.), it might be literally correct to say "Text is structure" because everything in the source document *is* text. And if you go farther down the ladder of abstraction even complex graphics and multimedia materials that are merely *referred* to in the source document reduce to strings of ones and zeroes, which can be represented in textual form. So it's text all the way down, or almost all the way down. John "Good design is accessible design." Please note our new name and URL! John Slatin, Ph.D. Director, Accessibility Institute University of Texas at Austin FAC 248C 1 University Station G9600 Austin, TX 78712 ph 512-495-4288, f 512-495-4524 email jslatin@mail.utexas.edu web <http://www.utexas.edu/research/accessibility/> http://www.utexas.edu/research/accessibility/ -----Original Message----- From: Gregg Vanderheiden [mailto:gv@trace.wisc.edu] Sent: Friday, June 04, 2004 12:05 am To: John M Slatin Subject: RE: 506 definition of structure Hmmm John? If text is structure what is information? Gregg _____ From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf Of John M Slatin Sent: Wednesday, June 02, 2004 10:15 AM To: w3c-wai-gl@w3.org Subject: 506 definition of structure At the 27 May telecon, Jason and I took an action item to work on the definition of structure. The definition appears below. Note: it is common practice for dictionary definitions to include examples that illustrate how the term is used in practice. In this spirit, the proposed definition refers to specific technologies (HTML, SVG, and MathML) that make it possible to indicate structural aspects of different kinds of content. We believe that it's clear from context that using these examples does not create an implicit requirement that SVG is the required format for all graphics or that MathML is the required format for mathematical expressions. Additional note: one of our goals was to bring this definition into alignment with our commitment to plain language. The definition as a whole receives a Flesch Reading Ease measure of 42.4 and a Flesh-Kinkaid Grade Level of 10.0 (which corresponds to the beginning of the second year of high school in the US). This is actually at the high end of the scale-- according to Canada's Northwest Literacy Council, a grade level of 10+ is appropriate if the document contains specialized technical information and the audience is familiar with the topic and has good literacy skills. However, the same group recommends a grade level of 7-9 for material intended for the general public that contains new terms and concepts or specialized subject matter. (Northwest Territories Literacy Council. A plain language audit tool. Available at http://www.nwt.literacy.ca/plainlng/auditool/cover.htm. The specific material about readability is at http://www.nwt.literacy.ca/plainlng/auditool/8.htm.) <proposed definition> Structure Structure includes all the parts of a Web resource and the way they are organized. The parts of a Web resource may include text, graphics, mathematical equations, multimedia, etc. Some parts may contain other parts or create relationships between two or more parts. Some relationships are hierarchical. Examples include sections and sub-sections of HTML documents, where each section or sub-section begins with a title that is marked as an HTML heading. The material in each section is logically related to the heading. The headings show the logical organization of the document. Some relationships are not hierarchical. Examples include links between two parts of the same document or between two documents. Mathematical expressions also have structure. It is possible to show this structure. For example, MathML can show the order in which calculations should be performed. Graphics may also have structure. Examples include flowcharts, diagrams, maps, and other complex images. SVG makes it possible to identify the structure of graphics. User agents may make the structure of Web resources evident to the user. </proposed definition> "Good design is accessible design." Please note our new name and URL! John Slatin, Ph.D. Director, Accessibility Institute University of Texas at Austin FAC 248C 1 University Station G9600 Austin, TX 78712 ph 512-495-4288, f 512-495-4524 email jslatin@mail.utexas.edu web <http://www.utexas.edu/research/accessibility/> http://www.utexas.edu/research/accessibility/
Received on Friday, 4 June 2004 09:58:52 UTC