Re: input document for discussion on Friday

John, all,

  comments back...

Am 31.10.12 12:59, schrieb John McCrae:
> Hi,
>
> Some comments
>
>     ex:lemon rdf:type ontolex:Lex.
>     ex:lemon ontolex:hasSense lemon_1.
>     lemon_1 owl:subClassOf <http://dbpedia.org/page/Lemon>.
>     ex:lemon ontolex:hasSense lemon_2.
>
> Thus :lemon_2 is an individual
>
>     lemon_2 owl:subClassOf ex:DefectiveItem.
>
> Thus :lemon_2 is a class
>
> This leads to a punning of the sense... is this intended?

Yes, intended to capture the dual role of a sense.

>
>     And further (not expressible in OWL2 DL):
>     ∀x; y lex(x; y) ∃s Sense(s) ^ hasSense(x; s) ^ representedBy(s; y)
>
>
> I really don't think we should go beyond OWL2 DL

We will not. This is simply not expressable in OWL2 DL. This is an axiom 
that might need to be ensured in implementations or not at all. To be 
discussed.
>
>      it is true that it blows up the complexity of the
>     model. However, it simplifies the usage of the model
>
> Surely this is a contradiction?

No, it's not. The model is in principle more complex, but people use 
always that subset that fits their need. They have their own simple view 
on a complex model.
>
>     I think this can be handled effectively by query expansion (as
>     above) in any
>     implementation of an API for the lexicon-ontology model
>
> Not all implementations will be query based... for example OWLAPI isn't

Sure, there will be different ways of implementing this. Query expansion 
is not the only one. Relying on OWL reasoning is another one.
SPARQL construct is another one. And a procedural API-specific 
implementation is another one. We could provide some recommendations on 
this. I am not suggesting that we ignore implementaiton, but that we do 
not put it at the centre of our discussions.
>
>     This can be done through SPARQL-construct 
>
> The construct query is:
>
> CONSTRUCT { ?entry ontolex:hasSense _:sense .
>                              _:sense ontolex:representedBy ?entity }
> WHERE {
>     ?entry ontolex:ref ?entity
> }
>
> Of course, this leads to issues as the constructed sense is a blank 
> node... I believe that like OWL we should advise against the use of 
> blank nodes for "concepts" within the lexicon. See 
> http://richard.cyganiak.de/blog/2011/03/blank-nodes-considered-harmful/ http://milicicvuk.com/blog/2011/07/14/problems-of-the-rdf-model-blank-nodes/ etc.
>
>     ex:lemon rdf:type ontolex:Lex.
>     ex:lemon ontolex:hasSense lemon_1.
>     lemon_1 ontolex:representedBy <http://dbpedia.org/page/Lemon>.
>     ex:lemon ontolex:ref <http://dbpedia.org/page/Lemon>. 
>
>     Then the question certainly is how many senses I get back with the
>     query.
>     Ideally, I would like to get one sense back.
>
> Yeah technically that is what should happen... however here we have to 
> apply the semantics of RDFS, in that the blank node we construct is 
> matched to lemon_1. Of course, the downside to this is that this is 
> non-polynomial to solve with generic solvers... and tricky in a 
> specialized implementation (also I think it is incompatible with OWL2-DL)
>
>     One question: do we want to model that for any pair of class and
>     lex, there
>     is at most one sense relating them? Can we do this in OWL?
>
> I would say no, I think we have found use cases for multiple sense 
> between the same entry/entity in /lemon/ (but can't remember at the 
> moment... it'll come to me)
>
As for in OWL... is this not it?
>
> ⊤⊑1.lex.Lex
>
No, this says that there is exactly one lexicalization per concept ;-)

> Regards,
> John
>
> On Wed, Oct 31, 2012 at 9:45 AM, Philipp Cimiano 
> <cimiano@cit-ec.uni-bielefeld.de 
> <mailto:cimiano@cit-ec.uni-bielefeld.de>> wrote:
>
>     Dear all,
>
>      I have compiled a brief document as input for our discussion on
>     Friday. We will discuss this proposal on Friday and collect
>     comments and objections.
>
>     Best regards,
>
>     Philipp.
>
>     -- 
>     Prof. Dr. Philipp Cimiano
>     Semantic Computing Group
>     Excellence Cluster - Cognitive Interaction Technology (CITEC)
>     University of Bielefeld
>
>     Phone: +49 521 106 12249 <tel:%2B49%20521%20106%2012249>
>     Fax: +49 521 106 12412 <tel:%2B49%20521%20106%2012412>
>     Mail: cimiano@cit-ec.uni-bielefeld.de
>     <mailto:cimiano@cit-ec.uni-bielefeld.de>
>
>     Room H-127
>     Morgenbreede 39
>     33615 Bielefeld
>
>


-- 
Prof. Dr. Philipp Cimiano
Semantic Computing Group
Excellence Cluster - Cognitive Interaction Technology (CITEC)
University of Bielefeld

Phone: +49 521 106 12249
Fax: +49 521 106 12412
Mail: cimiano@cit-ec.uni-bielefeld.de

Room H-127
Morgenbreede 39
33615 Bielefeld