- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Thu, 12 Nov 2009 21:55:43 +0000
- To: Bernard Vatant <bernard.vatant@mondeca.com>
- Cc: Antoine Isaac <aisaac@few.vu.nl>, Pat Hayes <phayes@ihmc.us>, SKOS <public-esw-thes@w3.org>
Bernard, Thanks for summing up the thread so nicely! And apologies for anyone who might be bored by this thread by now ... So you have me convinced that my skos:Concept labelled "Michelle Obama" is a "library business object" which is a different entity from Michelle Obama the living person. It follows that an owl:sameAs statement between the skos:Concept and the foaf:Person is inappropriate, because it conflates creation dates of different entities. On 12 Nov 2009, at 15:13, Bernard Vatant wrote: > OTOH, looking with librarian glasses on, DBpedia entries are also > somehow "concepts", since they could also bear Dublin Core stuff > like the first version of DBpedia in which they have been published, > number of related DBpedia concepts ... or any librarian workflow > record of the same kind. In this case, Richard could assert a > skos:exactMatch relationship between his entry and the DBpedia one. I'm intrigued. So could I say the following: <http://mydataset/433256> a skos:Concept; skos:closeMatch <http://dbpedia.org/resource/Michelle_Obama>. Note that the DBpedia resource *is* Michelle Obama the living person, typed as a foaf:Person, and bearing properties such as :spouse and :child. But I will just ignore that, just to see what rat's nest that will get me into. Because of the range of skos:closeMatch, the triples above imply the following: <http://dbpedia.org/resource/Michelle_Obama> a foaf:Person; a skos:Concept . So this would mean that there exists a concept that shares all properties (including creation date) with the person. I'm assuming that DBpedia does not assert any SKOS properties about the resource. Can a single URI refer to a person and to an equivalent concept at the same time? Anyone care to shoot holes into that idea? Richard > > But if the DBpedia entry is supposed to represent the thing herself, > as the predicates it bears, and the excellent (as usual) arguments > of Pat, seem to prove, we're back to the initial question : what > predicate should poor Richard (and myself) use if we want > nevertheless to express the fact that his specific record/entry/ > heading/concept is a proxy in his system for the person Michelle > Obama? We definitely miss, as I have kept stressing a lot of times > in the past, a specific vocabulary to indicate this level of > indirection, as also suggested in Danbri's answer. > And a side question is, if the DBpedia URI represents the thing > itself and not a DBpedia proxy of it, where do I put the above > workflow information? The date of publication of the DBpedia entry > vs the birth date of Michelle Obama ... > > Bernard > > > 2009/11/8 Antoine Isaac <aisaac@few.vu.nl> > Pat Hayes a écrit : > > > On Nov 5, 2009, at 2:51 PM, Antoine Isaac wrote: > > Hi Kingsley, > > when specifically does one use "skos:exactMatch" etc? Based on my > response John (few minutes ago), I am assuming that the partitioning > of so called Named Entities and Subject Matter Concepts was the line > of delineation sought in SKOS which is about Subject Matter/Heading > style Concept Schemes? > > > Well, as Leonard just put it, there can perfectly concepts for > persons (as part of authority files in Libraries, for example). > You could have a skos:Concept Mrs_Obama with a Library A as > dc:creator, and another Concept Michelle_Obama created by Library B. > Using owl:sameAs between those is certainly not ideal, as you end up > with one resource being created by two different agents, and > probably at different times, and so on. exactMatch fits that case. > > > If I follow this and your previous post, then sameAs will almost > never be true in the SKOS world, correct? > > > Yes. > > > The only case I can think of would be where a library puts a new > indexing system in place (for its existing records), and retains the > old one for legacy reasons, with sameAs links between the old and > new indices. > > > Not even then... If C1 is the legacy concept, and C2 the new one, > they would have different management info, perhaps different notes/ > definitions attached to them, semantic relations (broader/narrower/ > related) to different concepts... > So I would advise against using sameAs in such a concept. > sameAs would be rather used in case where different identification > schemes have been created for one concept, as in [1] > > > That is, co-reference between items in thesauri (both referring to > FLOTUS) is irrelevant to identity of the *concepts*. > > Do I have this more or less right? > > > Yes. Of course one can argue that it is a necessary condition, but > not a sufficient one. > By the way, Pat, I hope that the example [1] can shed a bit more > light in your quest for what a SKOS concept is. Especially you can > look at how the dcterms:created and dcterms:modified are used. > I guess that the general idea of Murano glass did not come into > existence at 1986-02-11T00:00:00-04:00. > SKOS concepts are very practical entities, almost > "documents" (albeit very specific, controlled documents) about more > general ideas. And of course these things can exist for persons, eg. > [2]. > > Antoine > > [1] http://id.loc.gov/authorities/sh85055118.rdf > [2] http://stitch.cs.vu.nl/vocabularies/rameau/ark:/12148/cb11944615b > > > > > > -- > Bernard Vatant > Senior Consultant > Vocabulary & Data Engineering > Tel: +33 (0) 971 488 459 > Mail: bernard.vatant@mondeca.com > ---------------------------------------------------- > Mondeca > 3, cité Nollez 75018 Paris France > Web: http://www.mondeca.com > Blog: http://mondeca.wordpress.com > ----------------------------------------------------
Received on Thursday, 12 November 2009 21:56:19 UTC