- From: Reto Gmür <reto@wymiwyg.com>
- Date: Tue, 23 Feb 2016 10:31:04 +0100
- To: semantic-web@w3.org
Hi Ross, While I agree with Antonie that the definition you suggest is semantically very weak I think a property as you would define range can have some pragmatic usefulness in some situation. But rather than redefining rdfs:range I suggest you use schema:rangeIncludes, which is defined as: "Relates a property to a class that constitutes (one of) the expected type(s) for values of the property." Cheers, Reto On Tue, Feb 23, 2016, at 09:37, Antoine Zimmermann wrote: > Ross, > > > The conclusion here is that Bioportal wrongly uses rdfs:domain. The > provenance ontology uses it correctly, and if DBpedia does not have > multiple domains or ranges, then no problem. > > There are certainly many more mistaken datasets with this respect, as > there are many other kinds of errors in datasets. There are also many > misinterpretations of HTML markups, mistakes in CSS files, and in fact, > all Web standards are misused to some extent. If the wrong use of > multiple domains / ranges was largely predominant, it would be a source > of concern for the standardisation groups of future versions of RDF. But > your observations in your email are not sufficient to indicate that. > > In any case, your suggestion: > > > "Where P has more than one rdfs:range property, then the resources > > denoted by the objects of triples with predicate P are instances of > > *some* class stated by the rdfs:range properties." > > would not work well with the inherent incompleteness of knowledge on the > Web and with the distributed nature of Web data. If I see: > > ex:myProperty rdfs:domain ex:Person . > > somewhere on the Web, I would like to conclude something about those > individuals who have the property ex:myProperty. Then I may find the > following: > > ex:myProperty rdfs:domain ex:Female . > > Now I know more than before, so I should infer more about those who have > the property. With your suggestion, every time I would know more about > the domain of a property, I would know less about those who have the > property. > > > Best, > AZ > > On 23/02/2016 03:36, Ross Horne wrote: > > Hi All, > > > > I'm wondering if many people here use multiple rdfs:domain/rdfs:range > > properties in RDF Schema? > > > > The RDF Schema spec is clearly worded: "Where P has more than one > > rdfs:range property, then the resources denoted by the objects of > > triples with predicate P are instances of *all* the classes stated by > > the rdfs:range properties." [similarly for rdfs:domain] > > > > However, this doesn't quite match the usage of multiple > > rdfs:domain/rdfs:range properties in several popular datasets. > > > > For example, in Bioportal, the property bpo:has_event has three classes > > indicated as its domain: bpo:person, bpo:event and > > bpo:disease_or_disorder. Following the wording of the spec, it would > > appear that any resource that appears in the subject position of a > > triple with property bpo:has_event is an instance of all three types > > bpo:person, bpo:event and bpo:disease_or_disorder. However, common sense > > says that the resource cannot simultaneously be a person, event and disease. > > > > Elsewhere, the provenance ontology avoids the problem by explicitly > > using owl:unionOf. For example, prov:wasInfluencedBy has rdfs:range such > > that it is the owl:unionOf the classes prov:Activity, prov:Agent and > > prov:Entity. DBpedia avoids the problem entirely, since I cannot find > > any multiple rdfs:domain/rdfs:range properties in their ontologies. > > > > The interpretation of multiple rdfs:range properties in the above > > datasets, either implicitly or explicitly imply an alternative spec such as: > > > > "Where P has more than one rdfs:range property, then the resources > > denoted by the objects of triples with predicate P are instances of > > *some* class stated by the rdfs:range properties." > > > > I'm wondering whether anyone else has observed this mismatch between the > > spec and real world datasets; and what the official line would be on > > avoiding this conflict? > > > > Regards, > > > > Ross > > > > > > Note I'm using the following prefixes in examples: > > bpo: <http://www.semanticweb.org/ontologies/2010/10/BPO.owl#> > > prov: <http://www.w3.org/ns/prov#> > > rdfs: <http://www.w3.org/2000/01/rdf-schema#> > > -- Reto Gmür reto.gmuer@zazuko.com
Received on Tuesday, 23 February 2016 09:31:30 UTC