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statements about resources vs. representations

From: Jonathan Rees <jar@creativecommons.org>
Date: Fri, 21 Nov 2008 08:58:22 -0500
Message-ID: <760bcb2a0811210558m5acbbbfdg45b973ed5949f52@mail.gmail.com>
To: "public-awwsw@w3.org" <public-awwsw@w3.org>

(Using "representation" in the AWWW sense here.)

Suppose I have a resource R, and for some reason I believe that
R dc:creator author:Charles_Dickens.

Now suppose that I do a GET to obtain a representation, and let F be
the fixed resource (see [1]) whose representation is this representation.
(I'll need a term for the coercion of representation to fixed resource, so
I'll say "the FR of the representation.")

Assuming good faith and proper functioning on everyone's part,
can I conclude that F dc:creator author:Charles_Dickens . ?  I suspect
so, but is this idea codified anywhere? Wouldn't this be part of AWWSW?

It seems to me that some properties will be shared between a resource
and its representations' FRs, while others aren't.

E.g. a property containsWord could easily be true of one representation
but not another (e.g. if the representations differ by language). Or,
more obviously,
one can meaningfully talk about the media type and content-length of a FR,
but not necessarily of its originating resource. Volatility is similar: the FR
is by definition not time-varying, but the resource may be.

I guess this is what Tim's "generic resources" memo [1] is saying.

Are there any properties of a resource that can be inferred
from its representations? That is, when I do a GET, do I
(or rather a stupid automated agent) learn anything
at all about what the resource is? I certainly don't learn anything
about, say, volatility, unless we're lucky enough to have
a credible assertion about it in the representation.
But I would guess that at least for things like authorship
(aspects of the content), if P and Q are disjoint classes,
and P applies to a resource's representation's FR, then you can conclude that
Q does not apply to the resource? That is, if you find that
any representation's FR's creator list consists of {George Eliot}, then
you know that the resource's creator list cannot be {Charles Dickens}.

This doesn't hold for volatility: volatile and nonvolatile are disjoint.

Conjecture: It seems that this analysis could continue, e.g. by helping
one to understand the domain, range, and arity (functional, inverse
functional, etc.) of various properties such as authorship and volatility
that one might apply to (information) resources.

[1] http://www.w3.org/DesignIssues/Generic.html

P.S. Is anyone interested in the AWWSW group any more?
Received on Friday, 21 November 2008 13:58:59 GMT

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