- From: Denny Vrandecic <denny.vrandecic@kit.edu>
- Date: Fri, 17 Dec 2010 11:10:27 +0100
- To: Martin Hepp <martin.hepp@ebusiness-unibw.org>
- Cc: Dave Reynolds <dave.e.reynolds@gmail.com>, Melvin Carvalho <melvincarvalho@gmail.com>, Semantic Web <semantic-web@w3.org>
And if you want to make make the statement that she owns two dogs, you can use the following statement (OWL 2 Functional Syntax): ClassAssertion( ObjectCardinality( 2 gr:owns vocab:Dog ) :Alice ) Cheers, Denny On Dec 17, 2010, at 10:59, Martin Hepp wrote: > Hi Melvin, > my two cents ;-) : > > 1. For owns, there is already a property read for use: http://purl.org/goodrelations/v1#owns > > 2. As Dave indicates, the irritation comes from the difference between "a" in English and in Turtle. In English, it's a quantifier, in Turtle it means "instance of". > > 3. Using DBPedia URIs as classes is problematic, because they usually represent topic instances. But Yago or Cyc will provide nice classes for dogs. > > 3. BNodes and resources identified by a full IRI both leave open whether both dogs are the same, so > > foo:Fix a vocab:Dog . > foo:Foxy a vocab:Dog . > foo:Alice gr:owns foo:Fix, foo:Foxy . > > does not yet make clear that these are two dogs; it could also just be two names / two identifiers for the same entity. > > For stating that, you would have to use owl:differentFrom : > > foo:Fix owl:differentFrom foo:Foxy . > > Then you could infer that she owns at least two dogs. > > Best > Martin > > > > On 17.12.2010, at 10:30, Dave Reynolds wrote: > >> On Fri, 2010-12-17 at 09:55 +0100, Melvin Carvalho wrote: >>> Apologies if this has come up before. I was wondering the best way to >>> model the following: >>> >>> Alice owns a dog. We choose to model it as follows. >>> >>> :Alice :owns a dbpedia:dog >> >> That's an RDF statement, maybe you meant: >> >> :Alice :owns [a dbpedia:dog] . >> >> I.e. there is something, which is a dog and which Alice owns. >> >>> >>> All is going well. >>> >>> Then Alice gets given a second dog. >>> >>> If we write: >>> >>> :Alice :owns a dbpedia:dog >>> :Alice :owns a dbpedia:dog >> >> :Alice :owns [a dbpedia:dog] . >> :Alice :owns [a dbpedia:dog] . >> >> is a reasonable graph, it is not lean since both those bNodes might >> correspond to the same dog but it is a graph with 4 statements not a >> graph with two statements. >> >> To convey that those are definitely different dogs then you can add an >> owl:differentFrom link: >> >> :Alice owns _:1 . >> _:1 a dbpedia:dog . >> :Alice owns _:2 . >> _:2 a dbpedia:dog . >> _:2 owl:differentFrom _:1 . >> >> Dave >> >> >> > >
Received on Friday, 17 December 2010 10:10:59 UTC