- From: Thomas Baker <baker@sub.uni-goettingen.de>
- Date: Mon, 24 Mar 2008 10:20:33 +0100
- To: SWD Working Group <public-swd-wg@w3.org>
Hi all, I'm not quite understanding the story we tell about the n-ary relation solution to label relations. The Primer says that relationships between labels are treated as first-order RDF resources. Each instance of this class, with its associated literals, may then ("later") be connected to concepts using skos:seeLabelRelation. About seeLabelRelation, SKOS Reference says simply: skos:seeLabelRelation rdfs:domain rdfs:resource . [1] and about the labels which are related, SR says only: "The rdfs:range of skos:labelRelated is the class of RDF plain literals." [3] So if we take the graph: ex:FAO skos:seeLabelRelation [ skos:labelRelated "baz"@en , "quux"@en ] . we have no basis to infer: ex:FAO rdf:type skos:Concept. or even: ex:FAO rdfs:label "baz"@en ; rdfs:label "quux"@en . Indeed, 8.6.2. [2] emphasizes that "there does not necessarily have to be any correspondence whatsoever between the lexical labels of a resource, and the labels involved in an associated label relation". Therefore, the following is consistent: <FooResource> skos:prefLabel "foo"@en ; skos:altLabel "bar"@en ; skos:seeLabelRelation [ skos:labelRelated "baz"@en , "quux"@en ] . If the association of an instance of the label relation class with particular concept is arbitrary, I'm also seeing no reason _not_ to take a label relation connected to <QuuxResource> as a statement about relations between labels of <FooResource>: <FooResource> skos:prefLabel "foo"@en ; skos:altLabel "bar"@en . <QuuxResource> skos:seeLabelRelation [ skos:labelRelated "foo"@en , "bar"@en ] . And I'm seeing no obvious reason why a label relation would not equally apply to a concept in another concept scheme, as in: <FooResource> skos:prefLabel "foo"@en ; skos:altLabel "bar"@en ; skos:inScheme <MyScheme> . <QuuxResource> skos:seeLabelRelation [ skos:labelRelated "foo"@en , "bar"@en ] ; skos:inScheme <AnotherScheme> . (In Amsterdam, Antoine asked "what if we mix two concept schemes? which scheme should we attach the label relationships to?" [6]). In sum, the Primer says that "some applications require the creation of explicit links between the labels associated to concepts". However, I do not understand whether the literals that are explicitly linked in an instance of the label relations class really are also explicitly being associated with the labels of the concept that is the subject of the seeLabelRelation statement. Or, alternatively, whether the instances of the label relations class merely amount to global assertions about the relationship between two literals in the world, wherever character-for-character identical literals may be found - whether linked to the same or different concept, within the same or different concept scheme, or even in an entirely non-SKOS context. Are the label relation resources perhaps intended as free-floating annotations that can be attached here or there in a pragmatic way, as for display or documentary purposes? Moreover, Margherita's point still stands that the "n-ary pattern" solution involves the duplication of information because label literals are written twice [5], which is not very pretty. Tom [1] http://www.w3.org/TR/2008/WD-skos-reference-20080125/#seeLabelRelation [2] http://www.w3.org/TR/2008/WD-skos-reference-20080125/#L3235 [3] http://www.w3.org/TR/2008/WD-skos-reference-20080125/#L3059 [4] http://lists.w3.org/Archives/Public/public-swd-wg/2007Jun/0120.html [5] http://www.w3.org/2006/07/SWD/wiki/SkosDesign/SKOS-XL?action=recall&rev=2 [6] http://www.w3.org/2007/10/09-swd-irc#T10-20-21 -- Tom Baker - tbaker@tbaker.de - baker@sub.uni-goettingen.de
Received on Monday, 24 March 2008 09:21:08 UTC