- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Tue, 17 Jan 2012 18:59:16 +0000
- To: Paolo Missier <Paolo.Missier@ncl.ac.uk>
- CC: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>, Paolo Missier <paolo.missier@newcastle.ac.uk>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
Hi Paolo, Stian To answer the transitivity question, we need to answer a question. Can an entity characterise different things? If yes, I agree transitivity does not necessarily hold. If no, transitivity holds. Professor Luc Moreau Electronics and Computer Science University of Southampton Southampton SO17 1BJ United Kingdom On 17 Jan 2012, at 16:37, "Paolo Missier" <Paolo.Missier@ncl.ac.uk> wrote: > Hi Stian, > > but really, alternateOf() is designed /precisely/ to provide to say that e1, e2, are different characterizations of the /same thing/. > > So if you assert > > alternateOf(paoloInCafe, customerOnRedChair) > > then you are indeed saying that they are the same thing, only using different characterizations. > And if you then also assert that > > alternateOf(stianInCafe, customerOnRedChair) > > then inferring that > > alternateOf(paoloInCafe, stianInCafe) > > is exactly what you want. If they are meant to be different things in the world, then one of the two assertions should not be there in the first place, right? > > I hope we can agree on this! > > --Paolo > > > On 1/17/12 3:14 PM, Stian Soiland-Reyes wrote: >> On Mon, Jan 16, 2012 at 14:31, Paolo Missier<Paolo.Missier@ncl.ac.uk> wrote: >> >>> I think of alternateOf as non-functional and transitive, which gives us >>> "clusters of alternates". We may later decide that it is convenient to add >>> properties that make a set of alternates into a lattice. >> No, not transitive. >> >> entity(customerOnRedChair, [prov:location="the red chair in the cafe"]) >> entity(paoloInCafe) >> entity(stianInCafe) >> entity(paolo) >> entity(stian) >> >> specializationOf(paoloInCafe, paolo) >> specializationOf(stianInCafe, stian) >> >> alternateOf(paoloInCafe, customerOnRedChair) >> alternateOf(stianInCafe, customerOnRedChair) >> >> >> but we probably don't want to then infer: >> alternateOf(paoloInCafe, stianInCafe) >> >> and certainly not: >> alternateOf(paolo, stian) >> >> .. neither did overlap the old characterisation intervals, and are >> different 'things' in the world. >> >> >> however, if Paolo and Stian did not sit anywhere else but in the red >> chair, we can also have: >> >> >> specializationOf(paoloInCafe, >> customerOnRedChair)specializationOf(stianInCafe, customerOnRedChair) >> this implies that for the duration of paoloInCafe, it was also >> customerOnRedChair. >> > > > -- > ----------- ~oo~ -------------- > Paolo Missier - Paolo.Missier@newcastle.ac.uk, pmissier@acm.org > School of Computing Science, Newcastle University, UK > http://www.cs.ncl.ac.uk/people/Paolo.Missier >
Received on Tuesday, 17 January 2012 19:00:26 UTC