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Re: ACTION Bijan: to work on "closeOver" work-alike with

From: <jos.deroo@agfa.com>
Date: Mon, 7 Mar 2005 22:32:39 +0100
To: bparsia@isr.umd.edu
Cc: kendall@monkeyfist.com, DAWG Mailing List <public-rdf-dawg@w3.org>
Message-ID: <OFC65A1FA3.9070A7FB-ONC1256FBD.0072537D-C1256FBD.00765855@agfa.com>

Bijan wrote:
> On Mar 7, 2005, at 1:47 PM, Kendall Clark wrote:
>
>> On Mon, Mar 07, 2005 at 10:55:45AM -0500, Bijan Parsia wrote:
>>
>>> If the action was to show the feasibility, then it is completed.
>>
>> I think I understand what you've done. But my only concerns are
>>
>>   1. Jos's case of being able to say that a graph is closed over an
>>      arbitrary (?) set of rules
>
> They just need an URI denoting them as an individual. That could be a 
> member of the class Expressivity.

OK, URI's are fine and what I did last 5 years was using such
expressivities which can be passed as command line argument
and have an internal mapping to load appropriate rule sets

else if (el.verb.startsWith(RDF)) return 
"http://www.agfa.com/w3c/euler/rdf-rules.n3";
else if (el.verb.startsWith(RDFS)) return 
"http://www.agfa.com/w3c/euler/rdfs-rules.n3";
else if (el.verb.startsWith(XSD)) return 
"http://www.agfa.com/w3c/euler/xsd-rules.n3";
else if (el.verb.startsWith(OWL)) return 
"http://www.agfa.com/w3c/euler/owl-rules.n3";

on top of that (for builtins, owl comprehension axioms, ...)
one can also source triples from

<http://www.w3.org/2000/10/swap/log#kb>
<http://www.w3.org/2000/10/swap/math#kb>
<http://www.w3.org/2000/10/swap/string#kb>
<http://www.w3.org/2002/07/owl#kb>


>>   2. the point that Bijan raises in a later message; that, for
>>      example, a graph may be closed over only the "interesting" subset
>>      of, say, RDFS entailments... Maybe there's not a real need to be
>>      able to say something this specific in the service description,
>>      but I can imagine a client taking "RDFS closure" in a strong way,
>>      querying for some triple that's inferred by one of the RDFS
>>      entailment rules that a particular graph *doesn't* implement...
> [snip]
> Well, I was thinking more of this.

me too :) and I remember that I had quite a hard time to do
just plain rdf inferencing (had to switch off all stuff like
builtin substitution of equals for equals, builtins, owl
comprehension, ...)

> Suppose I am 3Store and I always aggressively do RDFS closure. I can't 
> *not* query the RDFS closure.
>
> Suppose I am am Sesame, which can turn off RDFS closure, but have it on 
> too.
>
> These seem interestingly distinct.
>
> Now suppose there is a graph whose RDF and RDFS closure is identical 
> (are there any? hmm. I'll have to check).

never thought about that :)

> Then, these stores would 
> return the same hits. So it seems a little odd to say that 3Store 
> *doesn't* do RDF closure. It doesn't *filter out* RDFS (only) 
> entailments.
>
> I'm not sure it matters, but it did occur to me. In a class 
> representation of expressivity, you might want RDFExpr to be a subclass 
> of RDFSExpr and so on. But that wouldn't mean you could do *only* rdf 
> expr if you did RDFSExpr.

good

btw Bijan, in
http://www.mindswap.org/dav/ontologies/bijan/2005/dawg/TestClosedOver
I was not quite sure what was meant with
    :RDFSGraph  rdf:rest ();

> Cheers,
> Bijan.

-- 
Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Monday, 7 March 2005 21:33:23 GMT

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