- From: Guus Schreiber <schreiber@swi.psy.uva.nl>
- Date: Thu, 19 Jun 2003 11:19:00 +0200
- To: Ron Alford <ronwalf@wam.umd.edu>
- CC: public-webont-comments@w3.org
Ron Alford wrote: http://lists.w3.org/Archives/Public/public-webont-comments/2003May/0070.html > Hello, > Since there is an owl:AllDifferent, why is there not an owl:AllSame? I have a need for it on my current project. It would be nice for it to have similar semantics to owl:AllDifferent. > > Thanks, > - Ron Alford > > -- > Ron Alford, KB0NUV > http://volus.net/~ronwalf Ron, Thanks for your comment. We introduced a AllDifferent construct because of the exponential growth of the number of differentFrom statements; see Sec. 6.3 of OWL Reference [1] [[ For ontologies in which the unique-names assumption holds, the use of owl:differentFrom is likely to lead to a large number of statements, as all individuals have to be declared pairwise disjoint. ]] The case is different for sameAs, because sameAs only leads to linear growth of the number of statements. (due to the transitive nature of sameAs, the statements "a sameAs b" and "b sameAs c" already imply "a sameAs c"). Please respond, copying public-webont-comments@w3.org, as to whether you are satisfied with this response. Guus Schreiber [1] http://www.w3.org/TR/owl-ref/#AllDifferent-def
Received on Thursday, 19 June 2003 05:19:01 UTC