- From: Pat Hayes <phayes@ihmc.us>
- Date: Thu, 9 Jul 2009 22:23:27 -0500
- To: Ruth Dhanaraj <ruthdhan@gmail.com>
- Cc: Brandon Ibach <bibach@earthlink.net>, Bijan Parsia <bparsia@cs.man.ac.uk>, public-owl-dev@w3.org
On Jul 9, 2009, at 10:08 PM, Ruth Dhanaraj wrote: > There may be more than one property with domain C.... isn't it useful > to have it named for future use? Plus, the resulting info can be > expressed in plain RDF (without OWL)... > Sure. You obviously *can* define C and give it a name. But you are not *obliged* to. There are no rules either way. Do what you think is best. Pat Hayes > Ruth > > On Thu, Jul 9, 2009 at 6:57 PM, Brandon Ibach<bibach@earthlink.net> > wrote: >> That depends on what you hope to accomplish with your ontology and >> why >> you're stating a domain for your property. >> >> A property's domain causes an assertion of that property to trigger >> an >> assertion of the property's subject as a member of the class (C, in >> your example) given as the property's domain. Similarly, a subclass >> relationship (say, A subclassof C) causes an assertion of an instance >> as a member of A to trigger an assertion of that instance as a member >> of C. >> >> If the only other facts about the class C are that A and B are >> subclasses of it, then membership in that class carries no further >> semantics, so what have you gained? >> >> -Brandon :) >> >> On Thu, Jul 9, 2009 at 6:19 PM, Ruth Dhanaraj<ruthdhan@gmail.com> >> wrote: >>> Thanks for the info! Practically speaking, there's little difference >>> between the two, correct? If you're not concerned with excluding non >>> members of A and B, either syntax should suffice. >>> >>> Ruth >>> >>> On Thu, Jul 9, 2009 at 2:21 AM, Bijan Parsia<bparsia@cs.man.ac.uk> >>> wrote: >>>> On 8 Jul 2009, at 19:31, Ruth Dhanaraj wrote: >>>> >>>>> Hi, >>>>> >>>>> I've been trying to figure out how I would write a property and >>>>> say >>>>> its domain can be of type A *or* B. The RDF primer says that >>>>> specifying multiple domains is an AND, so that's out. >>>> >>>> Correct. >>>> >>>>> As far as I can tell, the semantics go something like this: >>>>> A subclassof C >>>>> B subclassof C >>>>> = C is a superset of A u B >>>>> >>>>> C unionOf (A B) >>>>> = C is A u B >>>>> >>>>> (then I can say that my property has domain C) >>>> >>>> You don't need the first two axioms when the latter is an >>>> equivalence axiom. >>>> >>>>> Is this correct? What's the recommended way to specify this? >>>> >>>> You can do this without introducing a new term (C). I.e., (in no >>>> real >>>> syntax) >>>> >>>> p domain unionOf(A B) >>>> >>>> Some versions of the Protege 3 series would do that by default >>>> when you >>>> added multiple domains (or ranges). >>>> >>>> Cheers, >>>> Bijan. >>>> >>> >>> >> > > > ------------------------------------------------------------ IHMC (850)434 8903 or (650)494 3973 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 mobile phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Friday, 10 July 2009 03:25:25 UTC