Hi Jim, On 4/2/12 7:29 PM, Jim McCusker wrote: > On Mon, Apr 2, 2012 at 2:14 PM, Luc Moreau <L.Moreau@ecs.soton.ac.uk <mailto:L.Moreau@ecs.soton.ac.uk>> wrote: > > On 2 Apr 2012, at 18:54, "Jim McCusker" <mccusj@rpi.edu <mailto:mccusj@rpi.edu>> wrote: >> >> 2. Is alternate reflexive or not? With time based definition it seems it is. With specialisation based definition it >> seems it may not be (depends whether any entity is always a specialisation of some entity) >> >> >> I think that it's okay for alternate to be reflexive. The controversy was whether or not specialization is. > Reflexivity is not obvious with your definition. Since for alternateOf (e,e) to hold, e needs to be specialisation of an > entity. Is it? > > > Good point. I'll leave it up to those who wish to have reflexivity for alternateOf to make their case. this is only an issue if alternate is defined in terms of specialization, because it implies that alternates have a common ancestor and thus there is a "top" of any specialization hierarchy. If we were to adopt James' proposal and make the two relations independent of each other, then this is no longer required, and there is an easier decision to be made. In this case, reflexivity is consistent with the definition: "alternateOf means that the two entities refer to the same changeable-thing" (interval overlapping condition removed) and I don't see a problem with it. --Paolo > > Jim > -- > Jim McCusker > Programmer Analyst > Krauthammer Lab, Pathology Informatics > Yale School of Medicine > james.mccusker@yale.edu <mailto:james.mccusker@yale.edu> | (203) 785-6330 > http://krauthammerlab.med.yale.edu > > PhD Student > Tetherless World Constellation > Rensselaer Polytechnic Institute > mccusj@cs.rpi.edu <mailto:mccusj@cs.rpi.edu> > http://tw.rpi.edu -- ----------- ~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, 3 April 2012 08:52:50 UTC