- From: eric hansen <ehansen@ets.org>
- Date: Wed, 19 May 1999 15:16:48 -0400 (EDT)
- To: w3c-wai-au@w3.org
I am convinced that the definitions of the priorities must focus on the people with disabilities. There was a suggestion that the definition of priorities use a term like "authors (including authors with disabilities)" when referring to the impact of violating a checkpoint. In this set of guidelines it is tempting to try to encompass a large set of users, i.e., all authors or all users. But I strongly encourage resisting the temptation. Our charter is to address disability access issues related to authoring tools. If we try to evaluate the impact on users without disabilities, we are out of our domain and our opinions have no more credibility or authority than the opinions of others. We should not dilute our influence by stepping over the bounds of our charter. As I have indicate earlier, it is fine to tell why we think the document might be helpful to nondisabled users (or "all users"), but the definitions of priorities and other such core elements of the document must focus strictly on people with disabilities. I believe that to have the priority definitions refer to people other than "individuals with disabilities" or "disability groups" will seriously dilute the influence and authority of the document. I suggest that we stay keep adhering to the principle that the priority level is determined by the impact on people with disabilities. To illustrated, following is extracted from my 5/19/99 revision of the 4/30/99 WATG document. 1.2 Checkpoint priorities {EH:I-001:(Issue number added 5/18/99. It was missing.)} Each checkpoint in this document is assigned a priority level that is based on the checkpoint's impact on people with disabilities. The specific meanings of the priorities vary between sections 2 and 3.{EH:I-011. Separation of sections} {EH:I-002:(Issue number added 5/18/99. It was missing.) Note separate sections (2 and 3)}Section 2 focuses on ensuring that the _content_ produced by the authoring tool is accessible. Following are the meanings of the priority levels for section 2: · Priority 1: This checkpoint must be implemented by authoring tools because violation of the checkpoint causes the content produced by the authoring tool to be impossible to access by one or more disability groups. · Priority 2: This checkpoint should be implemented by authoring tools because violation of the checkpoint causes the content produced by the authoring tool to be difficult to access by one or more disability groups. · Priority 3: This checkpoint may be implemented by authoring tools because violation of the checkpoint causes the content produced by the authoring tool to be somewhat difficult to access by one or more disability groups. {EH:I-012:5/19/99-15:09 hrs}The priority rating assigned to a section 2 checkpoint is based on the assumption that users of the content have typical (or average) skill levels in accessing and using Web content. {EH: I have ignored saying whether this is average for a disability group. I think one should assume an average of a broader population, though I don't think that it is necessarily worth stating.} Section 3 focuses on ensuring that the _authoring tools themselves_ are accessible. Following are the meanings of the priority levels for section 3: · Priority 1: This checkpoint must be implemented by authoring tools because violation of the checkpoint causes the authoring tool to be impossible to access by one or more disability groups. · Priority 2: This checkpoint should be implemented by authoring tools because violation of the checkpoint causes the authoring tool to be difficult to access by one or more disability groups. · Priority 3: This checkpoint may be implemented by authoring tools because violation of the checkpoint causes the authoring tool to be somewhat difficult to access by one or more disability groups. {EH:I-013:The priority rating assigned to a section 3 checkpoint is based on the assumptions that: · (1) {EH:I-014: Revised 5/19/99:}Users of the authoring tool have an skill level that is typical of successful users of that type of authoring tool. · (2) {EH:I-015:}Users employ the functionality of powerful intuitive interfaces (e.g., _WYSIWYG [What You See Is What You Get]) instead of less-intuitive (yet still powerful) interfaces (e.g., direct editing of HTML codes with a text editor). Without this assumption, virtually no checkpoint violation would be "impossible", since almost anything involving data can be performed with a text editor, albeit with extreme difficulty. Note that the priority rating system is not fully appropriate for authoring tools that rely only on direct editing of Web pages through a text editor; for such tools, authoring tends to be slower, but, as noted, virtually no task is "impossible". {EH: Reference to "generations" is probably not necessary: "Users generally employ third- or fourth-generation language (e.g., _WYSIWYG_ editing){EH: Check on usage}or similar functionality of the authoring tool instead of first- or second-generation languages (e.g., directed editing of HTML codes using a simple text editor). Note that the priority rating system is not fully appropriate for authoring tools that rely only on direct editing of Web pages through a text editor; for such tools, authoring tends to be slower, but virtually no task is "impossible".} The priority ratings for both section 2 section 3 are based on the assumptions that: · (1) {EH:I-016:}Content produced is of typical variety (information, education, entertainment, commerce). · (2) {EH:I-017:}Estimates of impact take into account the contrast in accessibility between consistent (pervasive) adherence and consistent violation of the given checkpoint. This "consistency" assumption is important to estimate the full impact. {EH: Note. A second, more subtle aspect of this is the "contrast" assumption, which is becomes especially important if one does not define a clear set of reference groups and begins looking at "subgroups" such as "deaf nonreaders." The "difference" assumption properly causes a checkpoint requiring visually-displayed text (which is extremely helpful for deaf readers) to have an undefined impact on deaf nonreaders, since there is no "contrast" in accessibility with or without adherence to the checkpoint. (Both conditions are equally innaccessible.)} · (3) {EH:I-018:}User agents (both to access the content in section 2 and as a typical component of authoring tools in section 3) are those available (or soon to be available) commercially to members of the disability group. · (4) {EH:I-019:}All priority ratings are based on a set of reference groups at least as extensive as the following: {EH:I-020: Insert the list of about 10-12 disability groups cited in the WCAG document} Furthermore, for both sections {EH:I-021:}: 1. Adherence to Priority 1 checkpoints is a basic requirement for accessible design. 2. Adherence to Priority 2 checkpoints removes significant accessibility barriers. 3. Adherence to Priority 3 checkpoints improves accessibility. {EH: Without this statement, it will take a long time for people to figure out the the meaning of the priority statements is so neatly partitioned by section. Please correct me if the meaning are not so easily partitioned between sections as I have indicated.} ============================= Eric G. Hansen, Ph.D. Development Scientist Educational Testing Service ETS 12-R Rosedale Road Princeton, NJ 08541 (W) 609-734-5615 (Fax) 609-734-1090 E-mail: ehansen@ets.org
Received on Wednesday, 19 May 1999 15:35:02 UTC