- From: Novacek, Vit <vit.novacek@deri.org>
- Date: Tue, 30 Oct 2007 18:10:27 -0000
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: <public-owl-wg@w3.org>, <rector@cs.man.ac.uk>
> > Anyway, this is a long way to say that I second the idea that we > > might want to revisit annotations w/respect to allowing a "minimal" > > semantics to them - so it woudln't break DL implementations, but > > would allow this feature to be more widely used by tools. > > +1 > > As you are agreeing, presumably you have some example tools and uses. > Could you share them with the WG? I'm sorry, I realised I should have given a more elaborated explanation already when reading the e-mail [1]... Maybe I do not have exactly the same "conceptualisation" of the "minimal semantics" expression used in the original e-mail - however, in the following I'll try to give initial elaboration of the reasons why I supported this, together with a sketch of applications that could make use of this "minimal semantics" of annotations. Note that these views are very roughly outlined at this stage and open to any discussion and comments - I'm also really open to any remarks pointing me to issues and materials that could help me with my concerns, since I'm quite new to this initiative and I'm very well aware of that. First of all, I do not object against the fact that annotations should not interfere with the DL-based inference in OWL1.1 - I think this should be separated, indeed. So, "minimal annotation semantics" != logical (model-theoretic) semantics of OWL1.1 recommendation in my view, therefore, no need for reasoners to try to cope with this "mess". However, I think it could be useful to come with a kind of very general granularisation of annotations in OWL1.1 - i.e., to propose and model basic annotation "types", possibly extensible by users. RDFS constructs like rdfs:label can obviously be re-used and sub-typed in this annotation hierarchy proposal. I can imagine the following example applications from the top of my head: i) Annotations can be part of the axioms, according to the document [2], Section 3. This would allow to connect for instance versioning-related information (time-stamp, information on version since which this axiom has been introduced into the ontology, etc.) not only to the ontology as such, but also to particular axioms. Of course, this could be done even now using rdfs:label or rdfs:comment, but these properties can be used for many other purposes, too. So, maybe it could be useful to have a common versioning-related annotation types in order to let applications make use of these features in uniformly defined (i.e., standard) way. I cannot really estimate practical impact of this, however, it may not be a complete non-sense in my opinion... ii) I have certain informal indications among the members of our institute that a standardised way of uncertainty representation (in OWL) would be a useful feature for their applications. According to the list referenced in [3], these features are de facto considered to be a part of rather far future (OWL 2.0), concerning their full incorporation into OWL (presumably into its model-theoretic semantics). However, having a special annotation type for expressing uncertainty (in a uniform way, not by arbitrary use of the generic annotation properties, again) would allow for this already now. The DL reasoners can safely omit such information in annotations, but applications that would like to make use of uncertainty measures associated with particular axioms could actually do it then, utilising a common way of uncertainty representation in OWL1.1, using a dedicated type of annotations. No matter whether they'd use the uncertainty measures just for ranking axioms in user interfaces, or for fuzzy-DL reasoning [4], or for whatever other purposes. Hope I made myself clear enough - feel free to ask for any further clarification if needed... Cheers, Vit [1] http://lists.w3.org/Archives/Public/public-owl-wg/2007Oct/0368.html [2] http://www.webont.org/owl/1.1/owl_specification.html [3] http://lists.w3.org/Archives/Public/public-owl-wg/2007Oct/0347.html [4] http://owled2007.iut-velizy.uvsq.fr/PapersPDF/submission_12.pdf
Received on Tuesday, 30 October 2007 18:10:51 UTC