- From: Graham Klyne <GK@Dial.pipex.com>
- Date: Tue, 30 May 2000 15:05:36 +0100
- To: Pierre-Antoine CHAMPIN <champin@bat710.univ-lyon1.fr>
- Cc: RDF interest group <www-rdf-interest@w3.org>
At 04:14 PM 5/30/00 +0200, Pierre-Antoine CHAMPIN wrote: >Graham Klyne wrote: > > >I must appologise for the diagram not being clear. The intent was to show > > >the whole statement being the subject of the 'asserted by' property which > > >would, I think, be consistent with the RDF model. > > > > Ah, OK. Consistent if the statement is reified. > >Why should we make a difference between reifying a triple and reifying an arc, >that is : > > ___________ >| S -(P)-> O| S -(P)-> O >|___________| | > | (assertedBy) > (assertedBy) | > | v > v Someone > Someone > > (fig 1) (fig 2) > >for me, both representation have the same meaning, >even though M&S uses fig.1, I find fig.2 more readable > >NB : in fig.2 I'm not annotating property P ! I'm annotating this one arc >(the one labeled with P, going from S to O... looks like a triple, doesn'it ?) But I don't know how to represent fig 2 within the current RDF graph model ... (P) is an arc, not a node, and the model supports only arcs that originate in node resources. Fig 2 can be treated as a convenient shorthand for S-(P)->O, PLUS its reification, PLUS the arc 'assertedBy' from the root resource of the reification to 'Someone'. I happen to quite like the direct arc-from-property approach, but it's not RDF as we know it. The recent posting about: <property rdf:ID="id">... suggests a way of representing this, which would map into a formal model consisting of quadruples -- almost the same as RDFM&S, section 5, except that the set called 'Statements' consists of quadruples of the form: {pred,subj,obj,ID} where ID is a name for the statement that can be used to construct the subject (or object) of some other statement. I see the approach of using hashes to name statements as an attempt to achieve the same effect within the current (triple-based) formal model. #g ------------ Graham Klyne (GK@ACM.ORG)
Received on Tuesday, 30 May 2000 14:25:30 UTC