- From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
- Date: Fri, 12 Apr 2002 11:33:32 +0100
- To: Patrick Stickler <patrick.stickler@nokia.com>
- Cc: Jeremy Carroll <jjc@hplb.hpl.hp.com>, RDF Core <w3c-rdfcore-wg@w3.org>
Er, do we have a disconnect here? Pat, if you're following this: I note your document that was at <http://www.coginst.uwf.edu/users/phayes/simpledatatype23-02-2002.html> is no longer there. Has it been moved? It would be good if it were kept available for a while, since that seems to be our last published point of consensus. Anyway, to resume normal programming... At 09:53 AM 4/12/02 +0300, Patrick Stickler wrote: >On 2002-04-11 18:53, "ext Graham Klyne" <Graham.Klyne@MIMEsweeper.com> >wrote: > > > At 12:22 PM 4/11/02 +0200, Jeremy Carroll wrote: > >> Now we add the range constraint on <age> > >> > >> <Jane> <age> "25" . > >> <film> <title> "25" . > >> <title> <range> <xsd:string> . > >> <age> <range> <xsd:integer> . > >> > >> We now have the film's title delivered as <xsd:string,"25"> the > woman's age > >> delivered as <xsd:integer,"25"> and they are different. > >> Hence we see defeasible reasoning: in the light of new information we > revise > >> our knowledge that Jane's age is <xsd:string,"25">, which in turn > causes us > >> to revise our conclusion that Jane's age and the film's title are the > same. > > > > My understanding of PatH's last proposal is that this graph is not > > satisfiable. More precisely: > > > > [[[ > > <Jane> <age> "25" . > > <age> <range> <xsd:integer> . > > ]]] > > > > is not satisfiable because "25" denotes a string and <xsd:integer> does not > > contain strings in its class extension. > >This is true if <range> equates to rdfs:range. I presumed it >equated to rdfd:range, in which case, there is no problem. > >It really will help, Jeremy, if you use the precise vocabulary >that we have come up with, especially if commenting on the current >WD, otherwise, we have no basis for mutual understanding. I know >that to some extent, you are trying not to beg the question by >keeping some terms somewhat ambiguous, but it makes it too hard >to know exactly what you mean. If you mean rdfs:range, please say so. >If you mean rdfd:range, again, just say so. etc. OK? Ummm... if you mean to interpret <range> as <rdfd:range>, then according to something Pat said a while ago [1], that has _no effect at all_ on the denotation of anything. That simply describes a syntactic constraint on literal labels in the RDF graph (which are satisfied by the above examples so can be dropped without having any any further effect on the semantics). #g -- [1] http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Mar/0241.html : [[ Right. The point is that rdfs:drange (or whatever we call it) really says nothing about the actual range: it ONLY invokes datatype checking. Now, one might reasonably expect that the actual range was 'in line' with the datatype checking, but that could be ]] [[ >According to section 5 of [1], taking account that literals denote >themselves, this means that > > <x,y> in IEXT(I(ex:age)) => z=L2V(I(datatype:decimal))(y) for some z No, it doesn't constrain the relational extension. What it does say is that ( <x,y> in IEXT(I(ex:age)) AND y a literal) => z=L2V(I(datatype:decimal))(y) for some z ie IF its a literal then its in the lexical space of datatype:decimal. But if its not, then nothing particular follows. ]] ------------------- Graham Klyne <GK@NineByNine.org>
Received on Friday, 12 April 2002 06:32:54 UTC