proposed response to OWL LC documents

This is a *proposed* response. Pls comment.
Guus

------------------------

Dear OWL WG,

The Semantic Web Deployment (SWD) Working Group has reviewed the 
OWL2 Last Call documents. We apologise that these comments are 
provided to you after the deadline. We hope you will still be 
able to consider them.

NOTE: Our comments are given from the perspective of the work of 
SWD on SKOS [1], as SKOS is based on RDF/OWL.


1. The SWD WG notes that some of the extensions provided by OWL2 
appear to be useful for SKOS. For example, property disjointness 
can be used in specifying the semantics for SKOS mapping 
relations. Although currently not needed in the SKOS semantics, 
we can foresee use cases for new property characteristics such 
as (a)reflexivity and asymmetry, e.g. for specifying 
application-specific specializations of SKOS semantic relations. 
  For alignment between SKOS and OWL DL the possibility to 
define axioms about annotation properties is perceived as useful.


2. The SWD WG is disappointed about the way the OWL2 material is 
presented, in particular the lack of using either an RDF/XML or 
an RDF triple representation of OWL2. Even the " New Features 
and Rationale" document [2] refrains from using such syntax. 
This makes the OWL2 documents inaccessible for the typical SKOS 
user. We request that the OWL WG remedies this situation.


3. The SWD WG notes that most OWL2 documents give the impression 
that OWL2 is just an extension of OWL1 DL, and not of OWL1 Full. 
For example, the introduction of  OWL2 Direct Semantics document 
states [3]:

   [[
     Since OWL 2 is an extension of OWL DL
   ]]

Only one document clearly makes the OWL2 DL and OWL2 Full 
distinction [4]. In our experience  OWL Full is the dominant OWL 
usage pattern for SKOS. We therefore request that the OWL2 
document are edited in such a way that whenever the term "OWL2" 
is used, it is used to refer to the OWL2 language as a whole 
(OWL2 DL and OWL2 Full). If OWL2 DL is meant, it should be 
explicitly marked as such. We also request that the nature and 
role of OWL2 Full are clearly stated in other central OWL 
documents, not just in [4].


We hope these comments are useful for you.

Best,
Guus Schreiber
on behalf of the Semantic Web Deployment Working Group

[1] http://www.w3.org/TR/skos-reference/
[2] http://www.w3.org/TR/2008/WD-owl2-quick-reference-20081202/
[3] 
http://www.w3.org/TR/2008/WD-owl2-semantics-20081202/#Introduction
[5] http://www.w3.org/TR/2008/WD-owl2-rdf-based-semantics-20081202/