Hi Bernard, thank you for pointing out the Geonames example and mapping.
I was too focused on connecting the Things that I've overlooked equivalence of Classes. What you suggest is a nice way to go without having to make bold claims about the actual equality of the classes that the two thing belong to.
Revisiting http://www.w3.org/TR/owl-ref/#equivalentClass-def now, "Real class equality can only be expressed with the owl:sameAs construct" also rings well.
-Sarven On 12-03-07 04:37 AM, Bernard Vatant wrote:
Hi Sarven You might be interested by the way I've mapped the Geonames feature codes, which are modelled as instances of a subclass of skos:Concept (hence OWL individuals) to equivalent classes in other ontologies. See [1] and [2]. The rationale is that most of the time when you assert that a owl:Thing T is "equivalent to" some owl:Class C, it means that being of rdf:type C is equivalent to have T as a value of some "typing" property. For example being an instance of the class "BlueThing" is equivalent to having "Blue" as value of some "hasColor" property. This can be modelled as in [2] using a owl:hasValue" restriction, avoiding the owl:sameAs temptation and keep all your ontology in safe OWL-DL land, this way : <owl:Class rdf:about="http://example.org/BlueThing";> <rdfs:label xml:lang="en">Blue Thing</rdfs:label> <owl:equivalentClass> <owl:Restriction> <owl:onProperty rdf:resource="http://example.org/hasColor"/> <owl:hasValue rdf:resource="http://example.org/Blue"/> </owl:Restriction> </owl:equivalentClass> </owl:Class> <skos:Concept rdf:about="http://example.org/Blue";> <skos:prefLabel xml:lang="en">Blue</skos:prefLabel> <skos:prefLabel xml:lang="fr">Bleu</skos:prefLabel> </skos:Concept> Hope this helps Bernard [1] http://www.geonames.org/ontology/ontology_v3.01.rdf [2] http://www.geonames.org/ontology/mappings_v3.01.rdf Le 7 mars 2012 07:43, Sarven Capadisli <[email protected] <mailto:[email protected]>> a écrit : Hi, I'm sure this is talked somewhere, I'd love a pointer if you know any: I often see resources of type owl:Class get paired with resources of type owl:Thing using owl:sameAs. As far as I understand, this is incorrect since domain and range of owl:sameAs should be owl:Thing. I'm tempted to change my resource that is a skos:Concept skos:exactMatch'ed with a resource of type owl:Thing, and use owl:sameAs. Sort of like "everyone else is doing it, it should be okay", and "don't need to fear the thought police". However, I don't wish to do that with a clear conscience, hence, I'd appreciate it if anyone can shed some light here for me and help me understand to make an informed decision based on reason (no pun intended). Related to this, I was wondering whether it makes sense to claim a resource to be of type owl:Class as well as of type owl:Thing, where may be appropriate, or one could get away with it e.g., a country. If this is okay, I imagine it is okay to use owl:sameAs for the subject at hand and point to yet another thing. Thanks all. -Sarven -- *Bernard Vatant * Vocabularies & Data Engineering Tel : + 33 (0)9 71 48 84 59 Skype : bernard.vatant Linked Open Vocabularies <http://labs.mondeca.com/dataset/lov> -------------------------------------------------------- *Mondeca***** 3 cité Nollez 75018 Paris, France www.mondeca.com <http://www.mondeca.com/> Follow us on Twitter : @mondecanews <http://twitter.com/#%21/mondecanews>
