- From: Uli Sattler <sattler@cs.man.ac.uk>
- Date: Wed, 7 Nov 2007 16:42:33 +0000
- To: Alan Ruttenberg <alanruttenberg@gmail.com>
- Cc: public-owl-wg@w3.org
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 16:49:42 UTC