- From: Paul Groth <p.t.groth@vu.nl>
- Date: Thu, 31 May 2012 14:43:28 +0300
- To: Graham Klyne <Graham.Klyne@zoo.ox.ac.uk>
- Cc: "public-prov-wg@w3.org" <public-prov-wg@w3.org>
Luc, Graham: I wonder if one can see hasProvenanceIn(entity, bundle, alias-for-entity) as a proxy for hasProvenanceIn(entity, bundle) alternate(entity, alias-for-entity) Is this a possible interpretation? Thanks Paul On Thu, May 31, 2012 at 11:09 AM, Graham Klyne <Graham.Klyne@zoo.ox.ac.uk> wrote: > On 30/05/2012 10:41, Luc Moreau wrote: >>> >> In my approach, retrieve bob:bundle4 to access provenance about alice:report1, >>> > >>> > But how can you, since alice:report1 is not in bob:bundle4? >>> > >>>>> *then* use the specializationOf information to infer that provenance for >>>>> ex:report1 is also true for alice:report1. >>> >>> OK, I should have said "retrieve bob:bundle4 to access provenance about >>> ex:report1" there. The rest stands. >> >> But again, how do you know where to find provenance for ex:report1. >> >> You seem to have >> hasProvenanceIn(alice:report1, bob:bundle4, -) >> specializationOf(alice:report1, ex:report1) >> >> This does not say which bundle I can find provenance for ex:report1. > > Maybe I was right first time... I've lost the context of this example. > > Moving on... > >>> What I think we should *not* do is add things to PROV-DM purely to support >>> operational concerns (like incremental discovery). That would be to have the >>> tail wagging the dog. >> >> I think we may put to much emphasis on 'incremental discovery' as per PAQ. >> >> The PROV data model in effect specifies a distributed graph structure >> (distributed across bundles I mean here, services are a side issue). >> To me, it is essential for the model to provide accurate linking across bundles >> so that the data structure can be navigated. > > I think this is a reasonable and appropriate way to frame the problem. > >> By accurate, I mean that I want to be able to link an entity in a bundle with >> another entity in another specific bundle. > > This seems to me to be a different requirement; viz "to link an entity ... with > *another* entity". If that's a requirement, I think it should be orthogonal to > the cross-bundle linking. > > What I do not argue against is the construct: > > hasProvenanceIn(entity, bundle) > > What I am questioning is the purpose of > > hasProvenanceIn(entity, bundle, alias-for-entity) > > Why is the former construct alone insufficient to "provide accurate linking > across bundles so that the data structure can be navigated"? > > (AT this point, we probably need to revisit the examples, but I'm out of time > right now.) > >> Without it, bundles are effectively not usable, and very quickly we will see >> constructs like the one I suggest, to aid this navigation >> of the graph, and we will have failed in achieving interoperability. > > <aside> > "interoperability" is not a simple binary property. No specification can > reasonably underpin total interoperability. What a spec can do is provide a > basis for interoperability for a particular set of activities (scope). Any > application will build upon a spec with additional elements (which may or may > not be interoperable with other applications). > > Of itself, by virtue of being technology neutral, PROV-DM *cannot* be regarded > as achieving interoperability - additional technology layers will always be > needed for that. It's a fairly common problem in standards development to try > and "boil the ocean", rather than focus on documenting a clear consensus. Each > standard is just part of a bigger ecosystem, and should focus (like good > software products) on achieving some clear goals really well and play well with > other components. > > None of this is arguing against the desirability of adequately describing a > "distributed graph structure" - I think that is a reasonable goal here - but not > because not doing so would mean "we will have failed in achieving > interoperability" - in these terms, we will always fail to achieve interoperability. > </aside> > > #g > > > -- -- Dr. Paul Groth (p.t.groth@vu.nl) http://www.few.vu.nl/~pgroth/ Assistant Professor Knowledge Representation & Reasoning Group Artificial Intelligence Section Department of Computer Science VU University Amsterdam
Received on Thursday, 31 May 2012 11:44:03 UTC