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Re: reopen ISSUE-97 and reclose next week - should interpretations be relative to a vocabulary

From: Peter Patel-Schneider <pfpschneider@gmail.com>
Date: Thu, 7 Mar 2013 08:23:10 -0800
Message-ID: <CAMpDgVzVhaUwYH7ojPyZEP7EzKx8jaf71QVLCUAQnAPVAK7VnQ@mail.gmail.com>
To: Antoine Zimmermann <antoine.zimmermann@emse.fr>
Cc: public-rdf-wg@w3.org
SPARQL has the notion of a scoping graph, which controls which names are
available, so I don't think that this is a counter-example.

It may be that scoping graphs are related to the notion of interpretations
being relative to vocabularies, but the two are not equivalent, as far as I
can see.

peter


On Thu, Mar 7, 2013 at 6:58 AM, Antoine Zimmermann <
antoine.zimmermann@emse.fr> wrote:

> Peter,
>
> Le 06/03/2013 19:30, Peter Patel-Schneider a écrit :
>
>  I propose that we reopen ISSUE-97 and resolve it differently at the
>> teleconference next week.
>>
>> ISSUE-97 concerns whether
>>
>> ex:john ex:age "22"^^xsd:integer
>> {xsd:integer}-entails
>> ex:john ex:age "+22"^^xsd:integer
>>
>
> This has been decided to be solved independently of ISSUE-97.
> Thinking about it, the idea to make the mapping IL partial is good if
> interpretations do not depend on a vocabulary, since it does not force all
> literals to denote.
>
>
>
>  or the empty graph RDFS-entails
>> ex:john rdf:type rdfs:Resource
>>
>> In the 2004 version of RDF these entailments do *not* hold, the first
>> because there are {xsd:integer}-interpretations where "22"^^xsd:integer is
>> in the vocabulary but "+22"^^xsd:integer is not.   I believe that all RDF
>> implementations do *not* work this way.  Instead they take the very
>> reasonable idea that all interpretations involved in the reasoning must
>> interpret all the vocabulary in both the LHS and the RHS.
>>
>
> I don't believe that all implementations make "ex:john rdf:type
> rdfs:Resource" true in all cases.
>
> Consider the following. According to SPARQL 1.1 with RDFS entailment
> regime:
>
> ASK WHERE { <myURI>  a  rdfs:Resource }
>
> must return false if <myURI> is not a term in the dataset.
> The easiest way to implement that is to use a reasoner that implements RDF
> 2004 Semantics. If one uses a reasoner that implements RDF 1.1 Semantics
> (as currently written), one has to be careful with such cases.
>
>
>
>  The semantics should be modified to make it clear that entailment should
>> work the way that everyone thinks it does.  The current editor's draft of
>> the semantics changed interpretations so that they are no longer relative
>> to a vocabulary, but instead interpret all IRIs and all well-typed
>> literals
>> (and no ill-typed literals).  I believe that no changes are needed in any
>> other WG document, and that the change conforms to the universal
>> implementation of RDF.   This change has the desired effect and should be
>> adopted by the working group.
>>
>
> Fair enough, we can agree on this with a resolution next week, if everyone
> approves.
>
>
> AZ
>
>
>
>> Peter F. Patel-Schneider
>> Nuance Communications
>>
>>
> --
> Antoine Zimmermann
> ISCOD / LSTI - Institut Henri Fayol
> École Nationale Supérieure des Mines de Saint-Étienne
> 158 cours Fauriel
> 42023 Saint-Étienne Cedex 2
> France
> Tél:+33(0)4 77 42 66 03
> Fax:+33(0)4 77 42 66 66
> http://zimmer.**aprilfoolsreview.com/<http://zimmer.aprilfoolsreview.com/>
>
>
Received on Thursday, 7 March 2013 16:23:38 GMT

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