- From: Bernardo Cuenca Grau <Bernardo.Cuenca.Grau@comlab.ox.ac.uk>
- Date: Mon, 22 Sep 2008 11:51:20 +0100
- To: OWL Working Group WG <public-owl-wg@w3.org>
Hi, This email addresses my action concerning the review of the conformance document. I have considered the latest version, which is integrated with the test document. http://www.w3.org/2007/OWL/wiki/Test#Conformance_.28Normative.29 Cheers, Bernardo ------ **Beginning of Section 2** I think the section is missing an introduction that explains what is the purpose and scope of the conformance definitions. Otherwise the content of the document can be confusing (see below). ** Section 2.1.1 ** I agree with Mike Smith's and Michael Schneider's comments about the document only mentioning the RDF syntax. For example, if we have an OWL 2 EL ontology in functional syntax that complies with the OWL 2 EL grammar as defined in the profiles document, is it then an OWL 2 EL document? The role of the RDF parsing process mentioned in the definition seems to me unclear in this case. It seems that the syntactic conformance definitions are only focused on and targeted towards the RDF syntax; however, the scope of these definitions should be clearly stated in the document to avoid confusion. I suggest two possible fixes: 1) To make it clear in the section that the syntactic conformance definition is only intended for ontologies in RDF 2) To change the definition of syntactic conformance to include all possible syntaxes **Section 2.2.1** The definitions of semantic conformance should be slightly rephrased. For example, the document says: ``*An OWL 2 DL entailment checker* is an OWL 2 entailment checker that takes OWL 2 DL ontology documents as input, and uses the Model Theoretic Semantics [OWL 2 Semantics <#ref-owl-2-semantics>]. It /MUST/ return True only when /O_1 / entails /O_2 /, and it /MUST/ return False only when /O_1 / does not entail /O_2 /. It /SHOULD NOT/ return Unknown. '' Should be rephrased in the following way: ``*An OWL 2 DL entailment checker* is an OWL 2 entailment checker that takes OWL 2 DL ontology documents as input. It /MUST/ return True only when /O_1 / entails /O_2 / with respect to the Model Theoretic Semantics [OWL 2 Semantics], and it /MUST/ return False only when /O_1 / does not entail /O_2 / with respect to the Model Theoretic Semantics. It /SHOULD NOT/ return Unknown. '' Similarly with the other definitions. ** Definition of the OWL 2 RL Conformance ** From the definition in the document it seems that a sound and complete OWL 2 DL reasoner may not be an OWL 2 RL entailment checker. I find this quite strange. According to the profiles document, OWL 2 RL can be seen as a syntactic fragment of OWL 2 (there is a proper grammar that defines such fragment). I think that the problem is again that the scope of the definitions is not clear in the document, which causes ambiguity. In the current situation, the profiles and conformance documents don't seem to be in sync with each other. I suggest the following solution. We should have two notions of conformance for OWL 2 RL: 1) OWL 2 RL Entailment Checker: an OWL 2 entailment checker that takes OWL 2 RL ontology documents as input, and uses the Model Theoretic Semantics [OWL 2 Semantics <#ref-owl-2-semantics>]. It /MUST/ return True only when /O_1 / entails /O_2 /, and it /MUST/ return False only when /O_1 / does not entail /O_2 /. It /SHOULD NOT/ return Unknown. 2) OWL 2 RL RDF Entailment Checker: defined as in the current conformance document Then we should show that there is a correspondence for OWL 2 RL ontologies (as in Theorem 1 in the profiles document).
Received on Monday, 22 September 2008 10:52:10 UTC