- From: Giorgos Stoilos <gstoil@image.ece.ntua.gr>
- Date: Mon, 12 Mar 2007 18:57:01 +0200
- To: "'Boris Motik'" <bmotik@cs.man.ac.uk>, "'Michael Schneider'" <m_schnei@gmx.de>
- Cc: <evren@clarkparsia.com>, <public-owl-dev@w3.org>
Oh I see now. You mean that we do now how to reason about asymmetric but not about antisymmetric properties. Best, G. Stoilos > -----Original Message----- > From: Boris Motik [mailto:bmotik@cs.man.ac.uk] > Sent: Monday, March 12, 2007 5:32 PM > To: 'Michael Schneider'; gstoil@image.ece.ntua.gr > Cc: evren@clarkparsia.com; public-owl-dev@w3.org > Subject: RE: Semantics of antisymmetric properties > > Hello, > > I would just like to point out an important issue: we currently don't know > how to reason with antisymmetric properties. In fact, we don't even know > whether reasoning in SROIQ with antisymmetric properties is decidable. > Hence, for the time being at least, I don't believe we have a choice other > than to rename antisymmetric into asymmetric. > > Sincerely yours, > > Boris > > > -----Original Message----- > > From: Michael Schneider [mailto:m_schnei@gmx.de] > > Sent: 12 March 2007 15:24 > > To: gstoil@image.ece.ntua.gr > > Cc: bmotik@cs.man.ac.uk; evren@clarkparsia.com; public-owl-dev@w3.org > > Subject: RE: Semantics of antisymmetric properties > > > > Giorgos Stoilos wrote on Mon, 12 Mar 2007: > > > > > I guess the true question is "what semantics where really meant to be > > > captured"? Those of asymmetric or antisymmetric properties? > > > > My opinion: I would prefer /antisymmetric/ properties (from "x p y" and > > "y p x" follows "x=y"). Then, to model some real asymmetric property > > like e.g. 'hasFather', I can easily add a "IrreflexiveObjectProperty" > > axiom to the ontology. On the other hand, I then do not get into > > problems with properties like 'locatedIn', where it could be ok to say > > that some 'Location' is 'locatedIn' itself. Adding a global > > 'ReflexiveObjectProperty' axiom to the ontology or define some local > > 'SelfRestriction' for the 'Location' class on that property would then > > be consistent. > > > > Cheers, > > Michael > > > > > And moreover, > > > which semantics are the implementations supporting at this point? > > Checking > > > with the reasoning algorithm in the SROIQ paper I get the feeling that > > it > > > was meant to capture antisymmetric and not asymmetric properties. > Thus, > > it > > > might be a mistake on the semantics and not on the name of them. > > > > > > Best, > > > G. Stoilos > > > > > >> -----Original Message----- > > >> From: public-owl-dev-request@w3.org [mailto:public-owl-dev- > > request@w3.org] > > >> On Behalf Of Boris Motik > > >> Sent: Thursday, March 08, 2007 11:11 AM > > >> To: 'Evren Sirin'; public-owl-dev@w3.org > > >> Subject: RE: Semantics of antisymmetric properties > > >> > > >> > > >> Hello, > > >> > > >> You are right; this is a kind of a bug. Namely, we have followed the > > SROIQ > > >> paper, in which they say "antisymmetric", but the definition of the > > >> semantics is exactly as in OWL 1.1. Probably we should change the > spec > > to > > >> call such properties asymmetric instead of antisymmetric. > > >> > > >> Sincerely yours, > > >> > > >> Boris
Received on Monday, 12 March 2007 16:57:43 UTC