Priorities & Impacts; Affected Groups

Date: 11 December 1998, 18:24 hrs
To: WAI-GL Page Authoring List Group
From: Eric Hansen
Re: Priorities & Impacts; Affected Groups

I wish to respond to Charles McCathieNevile's 5 December comments on my 3 
December "Suggestions" posting. Additional information is found in my 11 
Dec memo entitled "Priorities, Impacts, Etc." 

Charles' comments:

> Item-17. Priority-Levels
CMcCN:: As I see it the priority levels are essential. The reason for not
making them normative is that they may change over time. However deciding
that they can be shifted to take commercial pressures etc into account is
not a decision which has anything to do with producing accessible content
- it is a decision about the commercial/technical/practical feasability of
a particular project and a weighing of the various arguments about having
to provide accessibility. The scope  of the document is to tell people
what needs to be done to achieve accessible content.
EH:: 
> Item-21. Absence of Tactile Communication
CMcCN:: True. This is the problem with listing the people  who will be
affected - we will never have an accurate list in a document of workable
size. It may be worth referring to another informative document which
could be referred from each of the Guidelines documents (and anything
else). It may not be necessary. I don't know.

1. Priority and Impacts

I agree that some kind of rating of severity, importance, or impact rating 
is essential. In fact, I think that it is so important that we should try 
to include such a rating in the normative part of the page authoring 
guidelines.

The "Priorities" in the current page authoring guidelines are, I believe, 
global estimates of the importance of adhering to the techniques. These 
priorities are tied to techniques and are affected by issues such as 
feasibility/practicality/cost. I believe that these priorities are intended 
to cut across virtually all sets of users (disabled and nondisabled), all 
situations, and all possible delivery technologies at the time the 
priorities are issued (or in the near term after the priorities are 
issued). These priorities, being so changeable and tied to non-normative 
techniques, should be non-normative. 

On the other hand, I argued that "adjusted impact ratings," or some summary 
index derived from them, may be sufficiently stable to include in the 
normative part of the guidelines. As I outlined, these impact ratings would 
be indicators of the adverse impact of violations of the guidelines upon a 
relatively small list of groups of users, especially groups of users with 
disabilities (blind, deaf, deaf-blind, LD, low vision, physical disability, 
etc.). These impacts are intended to be independent of the cost of 
overcoming the negative impacts. (Note that these impacts meet Charles' 
criteria of avoiding, to a significant degree, issues such as 
"commercial/technical/practical feasibility.")
  
2. Affected Groups

I think that while we may necessarily give up on listing all the groups 
affected for "priorities," I believe that it is important and necessary to 
specify a small set of groups, especially disability groups, for primary 
focus for the "impacts."

My main point is that impacts are closely tied to the nature of problems 
faced by a specific, finite, and relatively stable list of disability 
groups. Because the basic nature of these groups changes relatively slowly, 
impacts might be stable enough to be normative.

Following is a suggested list of groups for which impacts would be 
estimated for each of the guidelines. Please see the main "Priorities, 
Impacts, Etc." memo for detail on how to generate the impact ratings.

Disability Groups:

Blind
All Low vision
All Low vision except color deficiencies
Color deficiencies
Deaf
Hard of hearing
Deaf-blind
All Learning disability
Learning disability without dyslexia
Dyslexia
Physical disability
Emotional disability
Cognitive disability
Photosensitive epilepsy (is there a supercategory for this?)
Tactile disability (?)

Non-Disability-Related Groups:

People whose language is not your own
Users of old browsers
etc.
etc.
===
=============================
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 Friday, 11 December 1998 18:45:43 UTC