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Re: Contextualization ---> Optional bundle in Specialization

From: Paul Groth <p.t.groth@vu.nl>
Date: Wed, 27 Jun 2012 19:39:14 +0200
Message-ID: <D3E622D9-46CE-411E-A3A6-2B0C90EF624F@vu.nl>
CC: Luc Moreau <L.Moreau@ecs.soton.ac.uk>, Provenance Working Group WG <public-prov-wg@w3.org>
To: Graham Klyne <graham.klyne@zoo.ox.ac.uk>
Hi Graham

These are two different urls so they identify different things. The fact that we add some properties like bundle or specializationof doesn't break anything. I can do that with any resource on the web, no?


Paul

On Jun 27, 2012, at 19:09, Graham Klyne <graham.klyne@zoo.ox.ac.uk> wrote:

> On 27/06/2012 10:49, Luc Moreau wrote:
>> All,
>> 
>> At the face to face meeting, we have agreed to rename contextualization and mark
>> this feature
>> at risk. Tim, Stephan, Paul and I have worked a solution that we now share with
>> the working group.
> 
> I'm afraid I still have a problem with this.
> 
> Considering your bundle tool:analysis01:
> [[
> bundle tool:analysis01
>     agent(tool:Bob-2011-11-16, [perf:rating="good"])
>     specializationOf(tool:Bob-2011-11-16, ex:Bob, ex:run1)
> 
>     agent(tool:Bob-2011-11-17, [perf:rating="bad"])
>     specializationOf(tool:Bob-2011-11-17, ex:Bob, ex:run2)
> endBundle
> ]]
> 
> The problem is that, if subject to RDF semantics for URI interpretation, I can 
> see no semantic distinction is possible between
> 
>   tool:Bob-2011-11-16
> and
>   tool:Bob-2011-11-17
> 
> I.e. they are both specializations of ex:Bob, and that is all we can know about 
> them, as (by the nature of the semantics of URI interpretation) the denotation 
> of ex:Bob that appears in ex:run1 is the same as the denotation of ex:Bob that 
> appears in ex:run2.
> 
> ...
> 
> I do, however, have a different compromise that provides a hook for introducing 
> possible semantics later, or in private implementations, without sneaking in 
> something that could well turn out to be incompatible with, or just different 
> than, what the RDF group may do for semantics of datasets.
> 
> The hook is this: simply allow attributes for the specializationOf relation, but 
> don't define a specific attribute for bundle.  This would allow you to do a 
> private implementation of the scheme you describe, but would not allow it to be 
> mistaken for something that has standardized semantics.  As in:
> 
>   specializationOf(tool:Bob-2011-11-17, ex:Bob,
>                    [myprivateattribute:bundle=ex:run2])
> 
> ...
> 
> In case you think I'm jumping at shadows here, I'll note that RDF has been here 
> before.  The original 1999 RDF specification described reification without 
> formal semantics.  Reification was intended to allow for capturing this kind of 
> information - i.e. to make assertions about context of use, etc - a kind of 
> proto-provenance, if you like.  But when the group came to define a formal 
> semantics for RDF, there were two possible, reasonable and semantically 
> incompatible approaches; looking at the way that reification was being used "in 
> the wild", it turned out that there was data out there that corresponded to both 
> of these (incompatible) approaches.  This was in the very early days of the 
> semantic web, so the harm done was quite limited.  I think a similar mistake 
> today would cause much greater harm.
> 
> I think the appropriate way forward is to take this tool performance analysis 
> use-case to the RDF-PROV coordination group, and ask that it be considered as 
> input when defining semantics for RDF datasets.  I would expect that whatever 
> semantic structure they choose, it should be able to accommodate the use-case. 
> Then, we should be better placed to create an appropriate and compatible 
> contextualization semantics for provenance bundles.  But until then, I think we 
> invite problems by trying to create a standardized data model structure without 
> standardized RDF-compatible semantics to accommodate this use-case.
> 
> #g
> --
> 
> Tracker, this is ISSUE-385
> 
> On 27/06/2012 10:49, Luc Moreau wrote:
>> All,
>> 
>> At the face to face meeting, we have agreed to rename contextualization and mark
>> this feature
>> at risk. Tim, Stephan, Paul and I have worked a solution that we now share with
>> the working group.
>> 
>> Given that contextualization was already defined as a kind of specialization, we
>> now allow an optional
>> bundle argument in the specialization relation. (Hence, no need to create a new
>> concept!)
>> 
>> See section 5.5.1 in the current Editor's draft
>> http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html#term-specialization
>> 
>> Feedback welcome.
>> 
>> Regards,
>> Luc
>> 
>> PS. Tracker, this is ISSUE-385
>> 
> 
Received on Wednesday, 27 June 2012 17:39:22 UTC

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