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Re: The Steven King Example

From: Murray Maloney <murray@muzmo.com>
Date: Fri, 24 Nov 2006 16:46:13 -0500
Message-Id: <5.1.1.6.2.20061124161952.09cf31e8@mail.muzmo.com>
To: public-grddl-wg <public-grddl-wg@w3.org>

At 07:58 PM 11/24/2006 +0000, Ian Davis wrote:

>OK, with a real property:
>
><rdf:RDF
>   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
>   xmlns:f="http://purl.org/vocab/frbr/core#">
>
>   <rdf:Description rdf:about="http://example.com/authors#king">
>     <f:creatorOf rdf:resource="http://example.com/books#stand" />
>   </rdf:Description>
></rdf:RDF>
>
>You can look http://purl.org/vocab/frbr/core#creatorOf up to get a 
>definition. This will tell you that the subject of this triple is q 
>f:ResponsibleEntity (which further lookup would tell you is either a 
>f:CorporateBody or a foaf:Person) and the object is a f:Work
>
>I don't know of any URIs that represent Stephen King or his book. I know 
>of some that represent web pages about those things.

That's interesting. Certainly an ISBN URI can relate to a manifestation of 
the book,
but you seem to be telling me that we currently have no way to refer to an 
actual
human being or a work -- as opposed to a particular manifestation of that work.

Even so, if I were to use http://www.stephenking.com/pages/works/stand/ and
http://en.wikipedia.org/wiki/Stephen_King/ , I would be able to make further
assertions about either. For example, I could assert that "The Stand" has 
numerous
ISBNs associated with it, or that Stephen King is the author of "Carrie". I 
could
then go on to infer that "The Stand" and "Carrie" have the same author because
their author properties are equivalent.

>However simply by stating the RDF above I am claiming that 
>http://example.com/authors#king represents the creator of the resource 
>identified by http://example.com/books#stand which is perfectly valid. 
>Just because you can't get representations of those resources from those 
>URIs doesn't mean it's broken, inappropriate or invalid.

Well, if you say so. But I don't see how to "follow my nose" to come to the 
conclusion that
the URIs actually refer to the same Stephen King and "The Stand" that I 
intended to refer to.
I don't see how this helps. You might just as easily say that subject="a" 
and object="b"
and "b" is the creator of "a".


>If I didn't want to assign a URI to each resource then I would use 
>indirection. This is where the primary topic stuff in the primer example 
>comes from. So, omitting the URI for the subject and using wikipedia as an 
>indirect reference (usual namespaces assumed):
>
>   <rdf:Description>
>     <foaf:isPrimaryTopicOf 
> rdf:resource="http://en.wikipedia.org/wiki/Stephen_King" />
>     <f:creatorOf rdf:resource="http://example.com/books#stand" />
>   </rdf:Description>
>
>You can look http://xmlns.com/foaf/0.1/isPrimaryTopicOf up to discover 
>what that property means (hmmm xmlns.com appears to be unavailable today)

That's OK. I had to look that up when Dan first used it. My nose was 
working then
and I cached a partial understanding of its meaning

>I could use indirection to eliminate the URI for the object. Using some 
>details of the frbr model (A Work is realized by an Expression which is 
>embodied in a Manifestation which are physical things with ISBNs and 
>publishers etc)
>
>   <rdf:Description>
>     <foaf:isPrimaryTopicOf 
> rdf:resource="http://en.wikipedia.org/wiki/Stephen_King" />
> 
><f:creatorOf><f:Work><f:realization><f:Expression><f:embodiment><f:Manifestation>
>                 <foaf:isPrimaryTopicOf 
> rdf:resource="http://www.amazon.com/Stand-Expanded-First-Complete-Signet/dp/0451169530/" 
> />
> 
></f:Manifestation></f:embodiment></f:Expression></f:realization></f:Work></f:creatorOf>
>   </rdf:Description>
>
>Somewhat verbose for the introduction i suspect which is why I suggested 
>the very first form.

Yes, a bit verbose, and not simple at all. Do we really need to include all 
of the nested elements?
Wouldn't it be sufficient to say:

>   <rdf:Description>
>     <foaf:isPrimaryTopicOf 
> rdf:resource="http://en.wikipedia.org/wiki/Stephen_King" />
>     <f:creatorOf><f:Manifestation>
>                 <foaf:isPrimaryTopicOf 
> rdf:resource="http://www.amazon.com/Stand-Expanded-First-Complete-Signet/dp/0451169530/" 
> />
>      </f:Manifestation></f:creatorOf>
>   </rdf:Description>

Regards,

Murray
Received on Friday, 24 November 2006 21:47:01 GMT

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