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RE: MARC Codes for Forms of Musical Composition

From: Young,Jeff (OR) <jyoung@oclc.org>
Date: Tue, 6 Jul 2010 12:27:17 -0400
Message-ID: <52E301F960B30049ADEFBCCF1CCAEF5908DF4D2E@OAEXCH4SERVER.oa.oclc.org>
To: "Ross Singer" <ross.singer@talis.com>, "William Waites" <ww-keyword-okfn.193365@styx.org>
Cc: "Antoine Isaac" <aisaac@few.vu.nl>, "Karen Coyle" <kcoyle@kcoyle.net>, <public-xg-lld@w3.org>, "List for Working Group on Open Bibliographic Data" <open-bibliography@lists.okfn.org>, "public-lld" <public-lld@w3.org>
Let me address Ross' question before attempting to argue that restraint
to a single rdf:type is good practice.

 

Here is the example in question:

 

http://purl.org/NET/marccodes/muscomp/sy.rdf

 

The owl:sameAs property asserts that these two URIs identify "the same
thing" (http://www.w3.org/TR/owl-ref/#sameAs-def):

 

http://purl.org/NET/marccodes/muscomp/sy#genre

http://dbpedia.org/resource/Symphony

 

The 1st URI responds with this statement:

 

<http://purl.org/NET/marccodes/muscomp/sy#genre> rdf:type
<http://purl.org/ontology/mo/Genre>

 

The 2nd URI responds with this:

 

<http://dbpedia.org/resource/Symphony> rdf:type
<http://sw.opencyc.org/2008/06/10/concept/Mx4rwSmVfJwpEbGdrcN5Y29ycA> 

<http://dbpedia.org/resource/Symphony> rdf:type
<http://sw.opencyc.org/2008/06/10/concept/Mx4rvcNktpwpEbGdrcN5Y29ycA> 

 

Other rdf:type and owl:sameAs assertions cascade from there in dbpedia.

 

The following document isn't authoritative, but it discusses some of the
confusion surrounding owl:sameAs and may also help us sort out the
issues: 

 

http://www.w3.org/2009/12/rdf-ws/papers/ws21. 

 

Here is a quote:

 

"However, owl:sameAs does have a particular semantics of individual
identity, namely that the two individuals are exactly the same and so
share all the same properties." (original emphasis).

 

Since rdf:type is a property, I assume that an OWL reasoner should back
me up in my claim that Ross' example has multiple rdf:types. I just
downloaded Pellet and will report on the results once I figure out how
to run it. Hopefully, it will demonstrate how "share" involving
owl:sameAs plays out in practice.

 

Jeff

 

 

From: rxs@talisplatform.com [mailto:rxs@talisplatform.com] On Behalf Of
Ross Singer
Sent: Monday, July 05, 2010 10:03 PM
To: William Waites
Cc: Young,Jeff (OR); Antoine Isaac; Karen Coyle; public-xg-lld@w3.org;
List for Working Group on Open Bibliographic Data; public-lld
Subject: Re: MARC Codes for Forms of Musical Composition

 

My question was more based on the fact that I don't think anything
should have explicitly set multiple rdf:types in there.

 

If so, I'm curious to what they are.

 

-Ross.

On Mon, Jul 5, 2010 at 3:35 PM, William Waites <william.waites@okfn.org>
wrote:

On 10-07-05 10:35, Ross Singer wrote:
> Jeff, which resources have multiple rdf:types?  Of the muscomps, they
> should all only be mo:Genre.

I think it is perfectly valid to have multiple types. At the
very minimum everything is an rdfs:Resource whether
stated explicitly or not. If something breaks when it is
explicitly stated because it doesn't like multiple types I
think that something is itself broken...


Cheers,
-w

--
William Waites           <william.waites@okfn.org>
Mob: +44 789 798 9965    Open Knowledge Foundation
Fax: +44 131 464 4948                Edinburgh, UK

RDF Indexing, Clustering and Inferencing in Python
               http://ordf.org/

 
Received on Tuesday, 6 July 2010 16:28:22 GMT

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