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Re: [TF-ENT] URIs for entailment regimes in service descriptions

From: Ivan Herman <ivan@w3.org>
Date: Sun, 01 Nov 2009 17:25:31 +0100
Message-ID: <4AEDB67B.5090800@w3.org>
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>


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 GMT

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