- From: Dan Brickley <danbri@w3.org>
- Date: Thu, 6 Jan 2005 07:29:56 -0500
- To: "Matthews, BM (Brian)" <B.M.Matthews@rl.ac.uk>
- Cc: "'Dickinson, Ian John (HP Labs, Bristol, UK)'" <ian.dickinson@hp.com>, public-esw-thes@w3.org
* Matthews, BM (Brian) <B.M.Matthews@rl.ac.uk> [2005-01-06 12:12-0000] > > Ian, > > Point taken, I accept that there is an ambiguity - there > has been a long history of different names for this most > fundamental of thesaurus relationships in SKOS and its > predecessors! > > The interpretation we have settled on : > > C0 skos:narrower C1 > = > "C0 has the narrower concept C1" > > is more natural if you think of it "operationally" in the > directed labelled graph. To answer the query: > "From concept C0 find me all its narrower concepts". > then you follow all the skos:narrower properties from C0. > With the other interpretation, you would follow the skos:broader, > which would seem odd! FWIW this style is most consistent with that advocated in the RDF specs, which originally made this explicit by noting that we read "[subject] has a [property name] value which is [object]". eg. [restaurants] has a [narrower] value which is [vegetarian restaurants] I agree with Ian's point about the intuitiveness of this varying with choice of property name, at least in English. I have no intuitions about the situation in other languages, but it is worth remembering that English isn't the only language that'll be used for RDF property names, and that both schemas and practical examples are needed to make the author's intent clear. The chance of misinterpretation will vary from term to term, I think, and will vary depending on the complexity of the meaning we're trying to capture in the property name. http://www.w3.org/2001/sw/Europe/200404/i18n/jptofu-example1.xml is an example of some RDF/XML that uses Japanese kanji for property and class names btw. <foaf:Image rdf:about="http://example.com/photos/j1.jpg"> <foaf:depicts> <人間> <血液型>AB</血液型> </人間> </foaf:depicts> </foaf:Image> Knowing nothing of this, you might nevertheless figure out just from the RDF/XML structure that it is a description of an 'Image' that 'depicts' a thing of type '人間' that has a '血液型' property whose value is 'AB'. (hope my mailer deals with the UTF-8 OK; looks fine so far...) As an aside, I think rdfs:subPropertyOf and rdfs:subClassOf would much better have been named rdfs:superProperty, and rdfs:superClass but it's too late for that now. Dan > > colloquial English when stating a "narrowment" (:-) the narrower thing > > usually comes first. E.g: > > > > car narrower garage-door > > "My car is fortunately narrower than my garage door" > > > > garage-door narrower car > > "My garage-door has-narrower-thing my car" > > > > I know it's a different sense of 'narrow', but still ... > > > > RDFS solves this by adding a preposition to indicate the direction > > rdfs:subClassOf, rather than just rdfs:subClass which would have the > > same problem. I guess it's too late now to change the actual SKOS > > predicate name, but perhaps you could clarify the direction of the > > relationship in the documentation. The same comment applies to > > skos:broader, btw. > > > > Apologies if this has come up before. I did take a quick look at the > > archive but didn't see anything. > > > > Regards, > > Ian > >
Received on Thursday, 6 January 2005 12:29:56 UTC