- From: Paolo Missier <Paolo.Missier@ncl.ac.uk>
- Date: Mon, 16 Jan 2012 16:29:24 +0000
- To: James Cheney <jcheney@inf.ed.ac.uk>
- CC: 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>
James, Luc Here is Stephen's example from the use cases on the wiki: http://www.w3.org/2011/prov/wiki/File:Statestimescales.png here luc-at-mit is a specialization of luc-in-boston, with the intended meaning that it "further characterizes" the /description/ of the /same/ Luc thing. This means that - specialization, as James suggests, is indeed about descriptions and therefore not on par with alternateOf, and - specializationOf(e1, e2) only makes sense on the assumption that alternateOf(e1,e2) holds, that is, that e1, 2, are about the same thing (Luc in the example). this makes alternateOf(e1,e2) a necessary condition for specializationOf(e1, e2) to hold. At the same time, this rules out the semantics we have seen proposed earlier: alternateOf(e1,e2) == exists (c) : specializationOf(e1,c) and specializationOf(e2,c) and instead (IMO) calls for an interpretation domain in which you can express Things and you can say when Things t1, t2 are the same: alternateOf(e1,e2) only if (or "requires") I(e1) = I(e2) where I(e) is the Thing that e characterizes (sorry James I don't have your semantics in front of me, you may be saying the same thing) makes sense? -Paolo On 1/16/12 4:09 PM, James Cheney wrote: > In that case, would you (or Luc) also agree with describing "specializationOf(e1,e2)" as "e1 and e2 describe the same thing, and e1 is more detailed/specific than e2"? > > The concern I have about specalizationOf is that it is about the descriptions, not the described things. I can rationalize alternateOf as saying that "e1 and e2 refer to the same thing", which is almost what Luc wrote, but to rationalize specializationOf I need e1 and e2 to refer to descriptions, not things themselves. (I think it is this distinction that is one of the root causes of confusion here.) > > --James > > On Jan 16, 2012, at 4:06 PM, Paolo Missier wrote: > >> thing (we just crossed in the mail) >> -Paolo >> >> On 1/16/12 4:03 PM, Luc Moreau wrote: >>> Hi James, >>> >>> >>> To add on to this, did we really mean >>> >>> e1 and e2 provide two different characterization of the same entity >>> >>> or did we mean >>> >>> e1 and e2 provide two different characterization of the same THING? >>> >>> Luc >>> >> >> > -- ----------- ~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 Monday, 16 January 2012 16:29:50 UTC