- From: Philipp Cimiano <cimiano@cit-ec.uni-bielefeld.de>
- Date: Thu, 09 May 2013 21:51:20 +0200
- To: public-ontolex@w3.org
- Message-ID: <518BFE38.9060200@cit-ec.uni-bielefeld.de>
Hi Aldo, thanks for the clarification. This is indeed an interesting proposal. Philipp. Am 08.05.13 22:39, schrieb Aldo Gangemi: > Uhm, you're talking of two different things here. > Indeed SKOS in RDF-OWL has a semantics (intensional and extensional), > but this is true also for WordNet synsets, senses and words, as well > as for any other datum encoded in RDF-OWL. For that reason should we > then use only ontolex:reference for everything? > And I also see that subtle distinctions can be hard to digest to > non-experts. But no distinctions at all is an even worse problem. With > the design rationale that any OWL individual can be used as a > reference *in general* (in particular cases is of course perfectly > fine to treat them all as references), nothing can justify why SKOS > concepts are ok and others not. > I see two escapes: > > 1) we maintain the suggestion to use skos:exactMatch for mapping to > SKOS, explaining why and how, as it's common in design patterns for > software, ontologies, and data (people like being explained useful > things sometimes ;)) > 2) we collapse the properties, but we create an OWL axiom that states > e.g. the following general class axiom: > (ontolex:reference some skos:Concept) owl:equivalentTo > (skos:exactMatch some skos:Concept) > > Aldo > > On May 8, 2013, at 4:52:54 PM , Philipp Cimiano > <cimiano@cit-ec.uni-bielefeld.de > <mailto:cimiano@cit-ec.uni-bielefeld.de>> wrote: > >> John, >> >> of course skos:Concepts have a formal interpretation and thus an >> extension much as owl:Classes. >> >> So I am not assuming: >> >> :cat rdf:type skos:Concept ⊨ :cat rdf:type owl:Thing >> >> But a SKOS document is an RDF document and thus has an RDF >> Interpretation which also assign denotations to the URIs in the document. >> >> Further, of course SKOS documents has a semantics, which is defined >> in OWL. >> >> For example skos:transitiverBroader is defined as a OWL transitive >> property. >> >> And btw. skos:Concept is defined as being an owl:Class, i.e. >> skos:Concept rdf:type owl:Class (see axiom S1 in >> http://www.w3.org/TR/2009/REC-skos-reference-20090818/) >> >> So SKOS is as axiomatized as any other OWL ontology ;-) >> >> So we should not treat SKOS concept as being really different from >> OWL concepts at the lexicon level. Such distinctions are very subtle >> and people will not grasp this difference, having doubts on which >> property to use in a particular case. This will compromise the >> usability of the model IMHO >> >> Philipp. >> >> Am 08.05.13 21:36, schrieb John McCrae: >>> >>> >>> >>> On Wed, May 8, 2013 at 5:56 PM, Philipp Cimiano >>> <cimiano@cit-ec.uni-bielefeld.de >>> <mailto:cimiano@cit-ec.uni-bielefeld.de>> wrote: >>> >>> Dear all, >>> >>> I am not with Aldo and John here. >>> >>> I think introducing two different properties makes our model >>> unnecessarily complex. >>> >>> >>> Neither model introduces any new properties, the first allows >>> reference to have two domains (skos:Concept and owl:Thing) but means >>> only one (skos:Concept). The second model uses skos:exactMatch for >>> matching within a SKOS model and differentiates reference and means >>> by domain (owl:Thing and skos:Concept respectively). >>> >>> We said we use "reference" when the meaning is expressed by an >>> extensional entity where we defined extensional as "having an >>> extension in some model of the theory". I agreed to that. >>> >>> According to this, a particular skos:Concept (an individual) has >>> as much as an extensional interpretation as a particular >>> owl:Class, or an owl:Individual to stay at the same level. >>> >>> Eh? You are saying: "SKOS concepts have an extension in some model >>> of the theory". This seems very odd, SKOS does not have any formal >>> semantics, therefore how can it have models and extensions? The >>> reasoning seems circular, if I assume SKOS concepts have extensions >>> like an OWL entity then SKOS concepts are like OWL entities because >>> they have extensions. >>> >>> >>> Of course, a particular skos:Concept is an individual from an >>> RDF/OWL perspective and is also interpreted as some individual >>> in the corresponding domain, much like an owl:Individual. So a >>> model assigns some extensional interpretation to both >>> skos:Concepts and owl:Individuals. Where is then the essential >>> difference that prevents us using the same property for both then? >>> >>> Again, you are assuming that as >>> >>> :cat rdf:type skos:Concept ⊨ :cat rdf:type owl:Thing >>> >>> Ergo, :cat has an extension in OWL. But this only true because you >>> applied an OWL reasoner, and more importantly the meaning has >>> changed: the OWL reasoner has only indicated that there are is a >>> (individual) thing (the genus of cats), where as the SKOS concept >>> intended an extension as the class of cats. >>> >>> >>> Surely, skos:Concept are per definition "intensions", but >>> technically they are extensional entities according to our >>> definition, i.e. owl:Individual or rdf:Thing. >>> >>> Further, it is perfectly fine for a skos:Concept to be an >>> owl:Class (see >>> http://www.w3.org/TR/2009/REC-skos-reference-20090818/) >>> >>> >>> True, but more importantly a skos:Concept can also be an >>> owl:DatatypeProperty, an owl:ObjectProperty and an owl:Thing. The >>> difference is the underspecification. >>> >>> >>> What do we use then? "reference" or "means"? ;-) >>> >>> >>> Treating skos:Concept and owl:Class as different types of >>> meaning seems too subtle for people who want to use the model in >>> practice as they will always wonder which is the right property >>> to use. >>> >>> >>> Regards, >>> John >>> >>> >>> Philipp. >>> >>> Am 08.05.13 13:08, schrieb John McCrae: >>>> Hi Aldo, >>>> >>>> Names in the previous example are not fixed of course. I also >>>> don't like "means" that much I just haven't got a better >>>> alternative yet. (synset is too WordNet-specific, >>>> means/meaning/concept are too broad) >>>> >>>> Regards, >>>> John >>>> >>>> >>>> On Wed, May 8, 2013 at 1:02 PM, Aldo Gangemi >>>> <aldo.gangemi@cnr.it <mailto:aldo.gangemi@cnr.it>> wrote: >>>> >>>> Hi, I agree with John, we really seem on the same wave now >>>> :), in fact I agree with Model 2 being far better. >>>> Only, should we really use ontolex:means to link senses and >>>> synsets? It's a bit too broad as a name for a specific >>>> relation like that, isn't it? >>>> >>>> Aldo >>>> >>>> On May 8, 2013, at 6:37:22 AM , John McCrae >>>> <jmccrae@cit-ec.uni-bielefeld.de >>>> <mailto:jmccrae@cit-ec.uni-bielefeld.de>> wrote: >>>> >>>>> Hi Jorge, all, >>>>> >>>>> Thanks for your comment, I agree this is an issue we >>>>> should discuss. I think that it is clearly wrong to >>>>> continue to treat skos:Concepts as ontological elements, >>>>> they aren't and we shouldn't really confuse them. The >>>>> question of whether we should still use SKOS terminologies >>>>> as systems of reference for the model also seems clear to >>>>> me (of course we should). >>>>> >>>>> The question then boils down to this essential question: >>>>> do we use the same property to reference both a >>>>> skos:Concept and an ontology entity? >>>>> >>>>> This leads to two variation on the model: >>>>> >>>>> Model 1. (Same property) >>>>> >>>>> With synsets >>>>> >>>>> :corn --ontolex:sense-> :corn_sense1 --ontolex:means-> >>>>> wordnet:corn_n_xxx _--ontolex:conceptualizes->_ fao:Corn >>>>> (a skos:Concept) >>>>> :corn --ontolex:sense-> :corn_sense1 --ontolex:means-> >>>>> wordnet:corn_n_xxx --ontolex:conceptualizes-> dbpedia:Corn >>>>> (a owl:Class) >>>>> >>>>> Without synsets >>>>> >>>>> :corn --ontolex:sense-> :corn_sense1 >>>>> _--ontolex:reference->_ fao:Corn (a skos:Concept) >>>>> :corn --ontolex:sense-> :corn_sense1 --ontolex:reference-> >>>>> dbpedia:Corn (a owl:Class) >>>>> >>>>> Model 2. (Different property) >>>>> >>>>> With synsets >>>>> >>>>> :corn --ontolex:sense-> :corn_sense1 --ontolex:means-> >>>>> wordnet:corn_n_xxx _--skos:exactMatch->_ fao:Corn (a >>>>> skos:Concept) >>>>> :corn --ontolex:sense-> :corn_sense1 --ontolex:means-> >>>>> wordnet:corn_n_xxx --ontolex:conceptualizes-> dbpedia:Corn >>>>> (a owl:Class) >>>>> >>>>> Without synsets >>>>> >>>>> :corn --ontolex:sense-> :corn_sense1 _--ontolex:means->_ >>>>> fao:Corn (a skos:Concept) >>>>> :corn --ontolex:sense-> :corn_sense1 --ontolex:reference-> >>>>> dbpedia:Corn (a owl:Class) >>>>> >>>>> With further linking valid of >>>>> >>>>> fao:Corn --ontolex:conceptualizes-> dbpedia:Corn >>>>> >>>>> >>>>> I prefer model two as it makes a clearer distinction >>>>> between terminologies and ontologies, doesn't require >>>>> linking two SKOS concepts with an ontolex property (which >>>>> we should avoid as it is not our job to fix SKOS) and >>>>> allows us to define a natural property for linking >>>>> terminologies to ontologies. >>>>> >>>>> Regards, >>>>> John >>>>> >>>>> >>>>> >>>>> On Fri, May 3, 2013 at 2:58 PM, Jorge Gracia >>>>> <jgracia@fi.upm.es <mailto:jgracia@fi.upm.es>> wrote: >>>>> >>>>> Dear Philipp, all >>>>> >>>>> I am not able to join the telco today, sorry. But let >>>>> me to formulate >>>>> a quick question about John's model >>>>> http://www.w3.org/community/ontolex/wiki/File:John-modelling.png); >>>>> maybe you can treat it today. >>>>> Following the previous discussions I can understand >>>>> the inclusion of >>>>> the new class "Synset / Concept". My doubt is: despite >>>>> the fact that >>>>> skos concepts could be represented with this new >>>>> class, can we >>>>> alternatively continuing treating skos concepts (of >>>>> external skos >>>>> ontologies) as "ontology entities"? (as in the IFLA >>>>> example presented >>>>> last week). For me this option is very natural, fully >>>>> compliant with >>>>> R3 "semantics by reference" and we shouldn't lose it. >>>>> >>>>> Best regards, >>>>> Jorge >>>>> >>>>> >>>>> 2013/5/2 Philipp Cimiano >>>>> <cimiano@cit-ec.uni-bielefeld.de >>>>> <mailto:cimiano@cit-ec.uni-bielefeld.de>>: >>>>> > Dear all, >>>>> > >>>>> > this is a gentle reminder that we will have our >>>>> regular ontolex telco >>>>> > tomorrow. >>>>> > >>>>> > I intend to discuss the model proposed by John on >>>>> the basis of the >>>>> > contributions of all of you. >>>>> > I would like to see if there is a chance that we >>>>> agree on this model as a >>>>> > building block for the further work. >>>>> > >>>>> > Here is a link to the conference metadata including >>>>> access details: >>>>> > >>>>> > >>>>> http://www.w3.org/community/ontolex/wiki/Teleconference,_2013.03.05,_15-16_pm_CET >>>>> > >>>>> > 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 >>>>> > >>>>> > >>>>> >>>>> >>>>> >>>>> -- >>>>> Jorge Gracia, PhD >>>>> Ontology Engineering Group >>>>> Artificial Intelligence Department >>>>> Universidad Politécnica de Madrid >>>>> http://delicias.dia.fi.upm.es/~jgracia/ >>>>> <http://delicias.dia.fi.upm.es/%7Ejgracia/> >>>>> >>>>> >>>> >>>> >>> >>> >>> -- >>> 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 > -- 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
Received on Thursday, 9 May 2013 19:51:52 UTC