- From: Uli Sattler <sattler@cs.man.ac.uk>
- Date: Wed, 7 Nov 2007 17:31:52 +0000
- To: Alan Ruttenberg <alanruttenberg@gmail.com>
- Cc: public-owl-wg@w3.org
...in a sense that adding it never changes the meaning/entailments of an ontology since such a subproperty chain is vacuously satisfied in every interpretation...possible. I doubt whether it would make sense, though. Cheers, Uli On 7 Nov 2007, at 16:53, Alan Ruttenberg wrote: > So wait, am I hearing that this feature *could* be part of OWL 1.1DL? > -Alan > > On Nov 7, 2007, at 11:42 AM, Uli Sattler wrote: > >> >> On 7 Nov 2007, at 15:23, Alan Ruttenberg wrote: >> >>> Uli, >>> >>> Do the same decidability issues arise if only the last property >>> on the chain is a datatype property? >>> >> >> not really, but semantically, it doesn't make sense to have >> datatype properties anywhere else but in the last place of a >> chain: a datatype value can only ever occur as the "filler" of a >> property (or "have in incoming property edge"), but never be >> "subject" of a property. >> >> Cheers, Uli >> >>> -Alan >>> >>> On Nov 7, 2007, at 8:32 AM, Jim Hendler wrote: >>> >>>> >>>> So we can allow this in OWL 1.1 Full, but not in OWL 1.1. DL >>>> since it is only related to decidability which is the primary >>>> differentiator between DL and Full. So I propose that we >>>> include this construct in 1.1 but make it clear that using it >>>> will take you to Full. >>>> Since this is on agenda for discussion at a meeting I cannot >>>> attend, I state for the record that RPI would oppose any closure >>>> of this issue that would not allow a property chain to end in a >>>> datatype property in the RDF realization >>>> -JH >>>> p.s. I realize now that my primary problem with the structural >>>> document relates to this DL v. Full issue, and will take that up >>>> in another thread. >>>> >>>> >>>> On Nov 7, 2007, at 5:12 AM, Uli Sattler wrote: >>>> >>>>> >>>>> Dear all, >>>>> >>>>> a few days ago, I sent this email below as an answer to Owl Dev >>>>> only, overlooking that I should have sent it to owl-wg as >>>>> well...so here it is with a bit of delay, cheers, Uli >>>>> >>>>> >>>>> On 5 Nov 2007, at 15:13, Uli Sattler wrote: >>>>>> >>>>>> Hi Michael, >>>>>> >>>>>> there are reasons why these sub-property chains are only made >>>>>> up of object properties: decidability in OWL (DL and 1.1) >>>>>> relies on the fact that "datatype consistency" can be checked >>>>>> for each object separately, without referring to other objects >>>>>> and the values of their datatype properties. If we would need >>>>>> to do this, we would more likely be in trouble, and would need to >>>>>> >>>>>> - be much more careful about what datatypes and datatype >>>>>> predicates to allow without loosing decidability and >>>>>> - use more complex reasoning mechanisms that have, to the best >>>>>> of my knowledge, only been described on paper and never been >>>>>> implemented or tested. >>>>>> >>>>>> So, I can see your use case, but I don't think we know enough >>>>>> about this yet. >>>>>> >>>>>> If you want to know more, check out >>>>>> >>>>>> Carsten Lutz and Maja Milicic. A Tableau Algorithm for >>>>>> Description Logics with Concrete Domains and General TBoxes. >>>>>> Journal of Automated Reasoning. To appear. >>>>>> http://lat.inf.tu-dresden.de/~clu/papers/archive/jar06.pdf >>>>>> >>>>>> Carsten Lutz. Description Logics with Concrete Domains - A >>>>>> Survey. In Philippe Balbiani, Nobu-Yuki Suzuki, Frank Wolter, >>>>>> and Michael Zakharyaschev, editors, Advances in Modal Logics >>>>>> Volume 4. King's College Publications, 2003. >>>>>> http://lat.inf.tu-dresden.de/~clu/papers/archive/aiml4.ps.gz >>>>>> >>>>>> Cheers, Uli >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On 2 Oct 2007, at 13:26, Michael Schneider wrote: >>>>>> >>>>>> >>>>>>> >>>>>>> Hi! >>>>>>> >>>>>>> It just stroke me that there seem to be only Sub/Object/ >>>>>>> PropertyChains in >>>>>>> the current OWL-1.1 draft [1]. Does anyone know if there is a >>>>>>> problem with >>>>>>> also having sub property chains of the form >>>>>>> >>>>>>> SubDataPropertyOf( >>>>>>> SubDataPropertyChain(R1 ... Rn-1 Dn) >>>>>>> D ) >>>>>>> >>>>>>> where Dn and D are DataPropertyS (having compatible datatypes >>>>>>> as their >>>>>>> ranges), while R1 ... Rn-1 are ObjectPropertyS? >>>>>>> >>>>>>> With such a SubDataPropertyChain, one could for instance >>>>>>> translate rules >>>>>>> like: >>>>>>> >>>>>>> ?x hasFather ?y AND ?y hasFamilyName ?fn >>>>>>> ==> ?x hasFamilyName ?fn >>>>>>> >>>>>>> with ?fn being an xsd:string, into an equivalent OWL axiom >>>>>>> >>>>>>> SubDataPropertyOf( >>>>>>> SubDataPropertyChain(hasFather hasFamilyName) >>>>>>> hasFamilyName ) >>>>>>> >>>>>>> In this case, the super property whould equal the final chain >>>>>>> property (both >>>>>>> 'hasFamilyName'). >>>>>>> >>>>>>> An example for a more general rule type (the analogon of the >>>>>>> 'uncle' rule) >>>>>>> would be: >>>>>>> >>>>>>> ?g containsUser ?u AND ?u hasUserID ?i >>>>>>> ==> ?g containsUserWithID ?i >>>>>>> >>>>>>> where ?g would stand for some user group. Here, the >>>>>>> DataPropertyS >>>>>>> 'hasUserID' and 'containsUserWithID' differ from each other, >>>>>>> because they >>>>>>> are intended to have a different meaning. >>>>>>> >>>>>>> Any ideas, if this feature has a chance to enter the family >>>>>>> of OWL-1.1 (or >>>>>>> 1.2 :)) axioms? Or did I overlook some fundamental issue here? >>>>>>> >>>>>>> Cheers, >>>>>>> Michael >>>>>>> >>>>>>> [1] OWL-1.1 Semantics >>>>>>> http://www.webont.org/owl/1.1/semantics.html#2 >>>>>>> >>>>>>> -- >>>>>>> Dipl.-Inform. Michael Schneider >>>>>>> FZI Forschungszentrum Informatik Karlsruhe >>>>>>> Abtl. Information Process Engineering (IPE) >>>>>>> Tel : +49-721-9654-726 >>>>>>> Fax : +49-721-9654-727 >>>>>>> Email: Michael.Schneider@fzi.de >>>>>>> Web : http://www.fzi.de/ipe/eng/mitarbeiter.php?id=555 >>>>>>> >>>>>>> FZI Forschungszentrum Informatik an der Universität Karlsruhe >>>>>>> Haid-und-Neu-Str. 10-14, D-76131 Karlsruhe >>>>>>> Tel.: +49-721-9654-0, Fax: +49-721-9654-959 >>>>>>> Stiftung des bürgerlichen Rechts >>>>>>> Az: 14-0563.1 Regierungspräsidium Karlsruhe >>>>>>> Vorstand: Rüdiger Dillmann, Michael Flor, Jivka Ovtcharova, >>>>>>> Rudi Studer >>>>>>> Vorsitzender des Kuratoriums: Ministerialdirigent Günther >>>>>>> Leßnerkraus >>>>>>> >>>>>>> >>>>> >>>> >>>> "If we knew what we were doing, it wouldn't be called research, >>>> would it?." - Albert Einstein >>>> >>>> Prof James Hendler http://www.cs.rpi.edu/~hendler >>>> Tetherless World Constellation Chair >>>> Computer Science Dept >>>> Rensselaer Polytechnic Institute, Troy NY 12180 >>>> >>>> >>>> >>>> >>>> >>> >> >
Received on Wednesday, 7 November 2007 17:38:49 UTC