Re: Publications about OWL (1 or 2) Full

On 25/05/11 12:47, Michael Schneider wrote:
> Hi!
>
> On Thu, 19 May 2011 Markus Krötzsch wrote:
>
>  >> What Markus says here I guess is that, in spite of the limitations of
>  >> the punning mechanism, a full-fledged OWL 2 DL reasoners will likely
>  >> infer more things than *currently existing* incomplete OWL Full
>  >> reasoners.
>  >
>  > Right.
>
> Not right! See my yesterday's mail:
>

Please be careful. The sentence is "What Markus says here I guess is 
that ..." and this is certainly right. Further careful reading will 
reveal that there is no claim made that any OWL DL tool will derive 
strictly more consequences than any OWL Full tool. I think this should 
be obvious. But a very light-weight RDF entailement-rule reasoner may 
miss other entailments that OWL (direct and RDF-based) semantics would 
give you, so it might well be that in some situations the DL reasoner is 
"more complete" for the RDF-based semantics of your input than any 
RDF-based semantics tool (I am aware of the subtle differences that the 
semantics have in both ways, but this might not be the main issue for a 
pragmatic decision).

As you rightly say, using owl:sameAs to align classes is not a good 
approach in direct semantics, since it would not entail 
owl:equivalentClasses. I already argued for this position, but 
deliberately selected a more complicated case in my email since the 
owl:sameAs issue would be relatively easy to work around (by 
[additionally] using equivalentClasses in modelling right away, or by a 
simple "syntactic" completion before passing things to a direct 
semantics tool). Inferred sameAs would not allow such a treatment. I 
think the paper on OWL 2 metamodelling that I pointed to gives quite a 
good idea of what is possible in direct semantics.

Regarding the rest of your email: the discussion there seems to grow 
into an argument to defend the usefulness of OWL 2 Full in general. I do 
not think that I have taken a position in this respect, although you 
read that into my statements. I have no intention to even argue against 
any of what you said, so let us just put this topic aside.

Best regards,

Markus

-- 
Dr. Markus Krötzsch
Oxford  University  Computing  Laboratory
Room 306, Parks Road, Oxford, OX1 3QD, UK
+44 (0)1865 283529    http://korrekt.org/

Received on Wednesday, 25 May 2011 20:14:19 UTC