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Title: Decision on the proposed term "Accessibility"
Creator: Tom Baker
Creator: Stuart Sutton
A proposal from the DCMI Accessibility Working Group for a
new element -- "Accessibility" -- was discussed at the Usage
Board meeting in Shanghai on 10 October 2004. As proposed,
"Accessibility" was defined as [1, see Topic 10]:
A reference to a machine-readable profile that describes
the qualities of a resource that can be used to match
the needs and preferences of a user as expressed in a
machine-readable user profile.
The preliminary decision of the Usage Board in Shanghai was
to approve "Accessibility" subject to a re-wording of the
definition along the following lines :
A description of the qualities of the resource in terms
of control, display and content that can be used to match
the needs and preferences of a user.
The decision was subject to the blanket qualification that
"Usage Board decisions are not considered official until
decision documents are finalized and published on the DCMI Web
site" . It was reported back to the Accessibility Working
Group on 15 October that the outcome was positive but that
additional work remained to be done .
The process of finalization, however, proved to be more
difficult than expected. An informal survey of colleagues
suggested that the proposed wording was open to multiple
interpretations. Attempts to correct this ambiguity revealed
even more fundamental questions about the meaning and intended
use of the element -- questions too substantial to resolve
by simple refinement of language and consequently beyond the
mandate of the Usage Board.
Though this subsequent discussion made the decision reached in
Shanghai seem premature, the Usage Board stood by its initial
affirmation of the crucial need of supporting accessibility
statements in a cross-domain manner. In response, the Working
Group suggested a revised definition for consideration at the
mid-year Usage Board meeting on 19 May 2005, changing the
name of the element from "Accessibility" to "Adaptability"
A statement describing characteristics of the resource
that affect how it can be adapted so it can be perceived,
understood or interacted with by users.
In Washington, the Usage Board felt that this definition
(and name) differed enough from the definition (and name)
originally proposed to qualify, in effect, as a new proposal.
Even if UB members could understand the path leading to this
result, it seemed necessary to put the proposal through the
standard procedure of discussion and approval by the wider
Accessibility/Adaptability community, along with a public
comment period, before it could be approved by the Usage Board.
The Usage Board feels it has no choice but to send the
proposal back to the Accessibility Working Group for further
consideration. In doing so, the UB emphasizes the importance
of clarifying how an Accessibility or Adaptability element fits
into the DCMI Abstract Model -- a specification which has since
the Shanghai meeting been approved as a DCMI Recommendation
-- As proposed, the element is intended to hold several
property-value pairs within a value string for a
single element. While the Dublin Core Structured Value
(DCSV) specification has at times been used this way in
implementations, experience has proven that encoding
multi-attribute descriptions of a resource sacrifices
interoperability to convenience. Equally problematic for
interoperability is the use of multi-element XML blocks
in an element value.
-- If the basic requirement is that of pointing from a Dublin
Core description to an "alternative description" of
the same resource, what is perhaps needed is a generic
mechanism for linking to an alternative description --
regardless of whether that description is written in XML,
EARL, or any other language. Such a mechanism has not yet
been considered as part of the DCMI Abstract Model; perhaps
it should be. This would be a question for consideration
by the DCMI Architecture Working Group.
-- In the meantime, the set of properties needed to describe
a resource from the standpoint of accessibility would seem
to overlap with the set of properties needed to describe
a resource using Dublin Core itself (e.g., Type, Format,
Language, and Relation). Accordingly, the alternative,
accessibility-oriented description pointed to from a Dublin
Core description could perhaps itself be an application
profile of Dublin Core.
The Board is aware that the Working Group considered
this overlap as it developed the proposal for a new
element. Nevertheless, it is felt that work on development
of such a profile could serve to better clarify the Working
Group's functional requirements -- both to itself and,
crucially, to users of an accessibility element. Working more
firmly within the context of the Abstract Model would allow
the creation of future proposals for DCMI properties and