- From: Chris Welty <cawelty@gmail.com>
- Date: Thu, 10 Sep 2009 10:59:03 -0400
- To: Jos de Bruijn <debruijn@inf.unibz.it>
- CC: RIF <public-rif-wg@w3.org>
I was under the impression that option #3 was specifically not chosen because it leads to some undesirable property in BLD/OWL-DL combinations. Also, doesn't BLD allow the range and domain of # to be much larger than OWL-DL does for type? You will also have a hard time convincing me that #3 is a bug fix. I prefer option 2, and I would include in the additional text that combinations that map type and subclass between BLD and OWL-2 remains a research topic. -Chris Jos de Bruijn wrote: > In RIF-RDF combinations, there is a one-to-one correspondence between > rdf:type statements and # statements, and ## statements imply > rdfs:subClassOf statements, so: > > a#b iff a[rdf:type -> b] and > a##b implies a[rdf:subClassOf -> b] > > > These correspondences also hold in RIF-OWL Full combinations, since > their semantics simply extends the semantics of RIF-RDF combinations. > > Now, since the semantics of RIF-OWL DL combinations is completely > different, these correspondences do not automatically carry over. In > fact, in such combinations there is no relationship between # and ## > statements in RIF, on the one hand, and typing and subclass statements > in OWL DL, on the other. A minimalistic approach was taken in the > specification of the semantics of RIF-OWL DL combinations: > -OWL class membership statements A(?x) correspond to RIF statements > ?x[rdf:type -> A] > -property value statements R(?x,?y) correspond to RIF statements ?x[R -> ?y] > > There are no further correspondences between statements in OWL DL and in > RIF. However, some users may expect to be able to use # and ## > statements to access OWL class membership; the document currently does > not explain that this is not possible. > We could do one of three things: > 1- leave things as they are, assuming that # and ## are not of interest > to users of RIF-OWL DL combinations > 2- explain the use of # and ## in the document (this would certainly not > be a substantive change, so we should not run into procedural problems) > 3- define the semantics of # and ## in RIF-OWL DL combinations in a > similar fashion as in RIF-RDF combinations: a one-to-one correspondence > between # and OWL class membership statements and implication between ## > and OWL subclassing. Technically, this is not a problem. In principle, > it would be a substantive change, but we might be able to argue that it > was a bug in the specification. > > I am fine with any of the options. Clearly, option 1 would be least > work for me, followed by option 3. > Opinions? > > Best, Jos -- Dr. Christopher A. Welty IBM Watson Research Center +1.914.784.7055 19 Skyline Dr. cawelty@gmail.com Hawthorne, NY 10532 http://www.research.ibm.com/people/w/welty
Received on Thursday, 10 September 2009 14:59:51 UTC