- From: Paolo Missier <Paolo.Missier@ncl.ac.uk>
- Date: Wed, 18 Jan 2012 13:47:00 +0000
- To: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>
- CC: "Myers, Jim" <MYERSJ4@rpi.edu>, Paolo Missier <paolo.missier@newcastle.ac.uk>, Luc Moreau <L.Moreau@ecs.soton.ac.uk>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
Stian still catching up... see inlined. Essentially, I believe the absence of "time" made your example slightly misleading. On 1/18/12 8:41 AM, Stian Soiland-Reyes wrote: > On Tue, Jan 17, 2012 at 17:29, Myers, Jim<MYERSJ4@rpi.edu> wrote: >> I can see how the definition you have leads to the consequence you state, but it seems like the use case here is one we should be able to support - someone reports on the activities of the customer-in-the-red-chair over time and others report that Paolo and Stian were in the chair at various times and we'd like to have enough prov information to allow users to figure out who did what. > Yes, I believed alternateOf would be the trick to link these entities, > even across different account. > > I might have been confused by thoughts from the earlier ivpOf. > > > The feeling I get now is that > > alternateOf(a,b) > > is simply a shortcut for > > specializationOf(a, x) > specializationOf(b, x) this is Graham's definition. We have been there. We discussed which property should be primitive, and we seemed to half-agree that this axiomatization leads to problems. > and in specializationOf(b, x) there is a strict hierarchical system of > entities characterising things in the world. that's what I called upper half-lattice earlier. That didn't go down very well either because it leads to an alternateOf black hole (so to speak). We discussed this with James a few days ago. > If specializationOf is transitive, then this could go 'all the way up'. exactly. > Taken to the extreme: It means that if you assert an entity that > characterises "everything that ever existed, concepts and real > physical world" , then any other entity (within the account) would be > a specialization of the everything-entity, and therefore every entity > would be an alternate of each other, and everything becomes "the same > thing in the world". that's what I mean by "black hole". You will admit mine is a more colourful description. again: I think the problem is that time was missing from your example --Paolo > > >> If alternateOf is not capable of doing this, do we have some other mechanism that can? Or is the use case out of scope? > The old ivpOf did this. > > Not sure if my use case is out of scope. I think it is confusing > because it blurs the distinction between classes ("Class of anyone who > sits in red chair") and instances ("The single concept of 'The > customer in the red chair'"). > -- ----------- ~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 Wednesday, 18 January 2012 13:47:29 UTC