- From: Ivan Herman <ivan@w3.org>
- Date: Sun, 01 Nov 2009 17:25:31 +0100
- To: Sandro Hawke <sandro@w3.org>
- CC: Axel Polleres <axel.polleres@deri.org>, Bijan Parsia <bparsia@cs.man.ac.uk>, Birte Glimm <birte.glimm@comlab.ox.ac.uk>, SPARQL Working Group <public-rdf-dawg@w3.org>
- Message-ID: <4AEDB67B.5090800@w3.org>
Sandro Hawke wrote: >> AFAIK, the intersection of RIF and OWL regarding datatypes is RIF. > > Indeed. We caught Ivan in the well-laid trap: Ouch! :-) Ivan > he misunderstook > rif:local and rif:iri as datatypes, but they are actually "symbol > spaces", much closer to elements of the syntax than datatypes. > > -- Sandro > > >> HTH, >> >> Axel >> >> On 1 Nov 2009, at 07:31, Ivan Herman wrote: >> >>> (I explicitly cc Axel here to put on his RIF WG member hat...) >>> >>> Hm. I must admit I did not really look into this, I simply took the >>> terms used in the RDF Semantics document; more exactly, took over the >>> URI-s RIF already uses. And you are right, this is not clear.... >>> >>> Bijan Parsia wrote: >>>> On 1 Nov 2009, at 10:57, Ivan Herman wrote: >>>> >>>>> Birte, >>>>> >>>>> I was not at the call, sorry about that. >>>>> What I try to propose to the SW Coordination Group is the >>>>> following set >>>>> of URI-s >>>>> >>>>> http://www.w3.org/ns/entailment/Simple >>>>> http://www.w3.org/ns/entailment/RDF >>>>> http://www.w3.org/ns/entailment/RDFS >>>>> http://www.w3.org/ns/entailment/D >>>> I'm sorry that I seem to be missing something, but what does D >>>> indicate >>>> exactly? The ambiguity that concerns me is that it could indicate >>>> that >>>> the system respects the semantics of "datatypes in general" or of a >>>> specific set of datatypes. >>>> >>>> I presume it's the latter and the requisite datatype map is from: >>>> http://www.w3.org/TR/rdf-mt/#dtype_interp >>>> ? >>>> >>>> But that's not very well specified. It would be better to use the OWL >>>> 2/RIF specs, I think, or some subset thereof. (E.g., we shouldn't >>>> leave >>>> open whether float and integer are disjoint.) >>>> >>> Sigh:-) >>> >>> I would probably take the intersection of the OWL and RIF. Ie, leave >>> out >>> owl:float and rif:local or rif:iri. Alternatively, we may restrict >>> ourselves to what SPARQL defines as operand data types (11.1 in the >>> current spec). >>> >>> Looking at the RIF document >>> >>> http://www.w3.org/TR/rif-rdf-owl/ >>> >>> RIF uses this URI to identify the common RIF-D model which... seems to >>> leave the concrete datatype map open. >>> >>>> (I wonder whether using "D" is the best thing to do here. The term >>>> "D-entailment" is pretty obscure as far as I can tell. And, in this >>>> case, would it also entail RDF semantics? RDFS? Do we really need >>>> RDF?) >>>> >>> The RIF document says: >>> >>> [[[ >>> The profiles are ordered as follows, where '<' reads "is lower than": >>> >>> Simple < RDF < RDFS < D < OWL Full >>> >>> OWL DL < OWL Full >>> ]]] >>> >>> where 'profiles' means (just to muddy the waters:-) the RIF profiles. >>> >>> The ordering makes sense but it is more than what the RDF Semantics >>> seems to say for D. Axel, can you try to remember the reasoning >>> behind this? >>> >>> If we want some sort of a compatibility (that is how the whole >>> discussion on having separate and general URI-s for these started!) >>> then >>> we might want to take that over. It makes sense. >>> >>> Whether SPARQL really needs a separate RDF entailment here is a >>> different question... I am not sure (but the URI would still exist) >>> >>> Cheers >>> >>> I. >>> >>> >>> >>> >>>> Cheers, >>>> Bijan. >>> -- >>> >>> Ivan Herman, W3C Semantic Web Activity Lead >>> Home: http://www.w3.org/People/Ivan/ >>> mobile: +31-641044153 >>> PGP Key: http://www.ivan-herman.net/pgpkey.html >>> FOAF: http://www.ivan-herman.net/foaf.rdf >> -- Ivan Herman, W3C Semantic Web Activity Lead Home: http://www.w3.org/People/Ivan/ mobile: +31-641044153 PGP Key: http://www.ivan-herman.net/pgpkey.html FOAF: http://www.ivan-herman.net/foaf.rdf
Received on Sunday, 1 November 2009 16:26:06 UTC