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Re: ISSUE 37+56

From: Guus Schreiber <schreiber@cs.vu.nl>
Date: Wed, 12 Mar 2008 16:33:33 +0100
Message-ID: <47D7F7CD.4020302@cs.vu.nl>
To: Antoine Isaac <aisaac@few.vu.nl>
CC: "Sini, Margherita (KCEW)" <Margherita.Sini@fao.org>, SWD WG <public-swd-wg@w3.org>



Antoine Isaac wrote:
> Hi Margherita, Guus
> 
> Actually I've been forwarded yesterday a case of 'broader causative'. So 
> I guess this would confim that your 'related causative' is not a 
> candidate for predefined specialization, if we follow what Guus decided 
> for 'related partitive'.
> 
> By the way my position on this specialization aspect is simple: let's 
> include nothing.
> First, it adds relation to SKOS
> Second, well, I feel that we're trying to do this to be more compliant 
> with standards like ISO2788. But if we do it half-way (broaderGeneric 
> and broaderInstantive but not broaderPartitive) that might look a bit 
> shaky, even if there are valid motivations for doing so.

Antoine, 

Sorry, my text was apparently not clear. It was my proposal to *keep* broader/narrowerPartitive (and drop the related part-of variant), because it is the intuitive one and also keeps the relation with ISO 2788. 

> 
> But if we include them anyway: I like very much the semantics Guus has 
> proposed for broaderGeneric and broaderInstantive.

On reflection, we might just define broaderGeneric and broaderInstantive as owl:equivalentProperty of resp. rdfs:subClassOf and rdf:type (and not as subproperties of these). 

Guus

> 
> Cheers,
> 
> Antoine
> 
>> Hi there,
>>
>> If this can help, I can see the following top-level concept-to-concept
>> relationships that may be implemented in skos, in addition to the one 
>> already
>> mentioned:
>>
>> - relatedCausative (all the ones like causes/isCausedBy,
>> benefitFrom/isBeneficialFor, affects/isAffectedBy, etc...)
>>
>> - relatedTermporal (all the ones like follows/precedes,
>> developsFrom/developsInto)
>>
>> - relatedEssive (all the ones like isUsedAs/isUseOf, 
>> isDerivedFrom/isSourceOf
>> , etc.)
>>
>> - relatedInstrumental (all the ones like growsln/isAGrowthEnvironmentFor,
>> isMeansFor /isPerformedByMeansOf, etc.)
>>
>> but, I can see that we would like to limit to "a limited number of 
>> predefined
>> specializations"... So maybe the aboves are just to keep in mind and will
>> just be implemented in SKOS with the simple "related"...?
>>
>> regards
>> Margherita
>>
>> -----Original Message-----
>> From: public-swd-wg-request@w3.org 
>> [mailto:public-swd-wg-request@w3.org] On
>> Behalf Of Guus Schreiber
>> Sent: 11 March 2008 15:59
>> To: SWD WG
>> Subject: ISSUE 37+56
>>
>>
>>
>> All,
>> Here are some thoughts about the specialization/extension issues.
>> Guus
>>
>> ISSUE 37 Skos Specialization 
>> http://www.w3.org/2006/07/SWD/track/issues/37
>> ISSUE 56 ReferenceSemanticRelationshipSpecializations
>> http://www.w3.org/2006/07/SWD/track/issues/56
>>
>> Here are some initial thoughts before proposing a resolution for these 
>> two
>> issues. I suggest we propose no drastic changes, basically saying:
>>
>> 1. There are a limited number of predefined specializations in the SKOS
>>    vocabulary, that are in common use in the thesaurus world
>> 2. Vocabulary owners can define their own specializations by defining
>>    subproperties of SKOS concepts, semantic relations and label
>>    relations. The SKOS Reference and Primer contain examples as 
>> guidelines
>>
>> Ad 1.
>>
>> The current SKOS extension module predefines 8 specializations: namely 
>> - broader/narrower-Generic/Instantive/Partitive
>> - related-hasPart/PartOf
>>
>> The problem I see is that these specializations define two different 
>> ways of
>> specifying part-whole relations. This may be very confusing. I suggest to
>> keep only the intuitive one, namely "broader/narrower Partitive". I 
>> assume
>> the "related" part-whole relations are typically used to link, for 
>> example,
>> concepts in a hierarchy of products with concepts in a hierarchy of
>> ingredients or materials. However, I suggest this should not be a
>> *predefined* specialization.
>>
>> Wrt the semantics of the specializations:
>> * broaderGeneric
>>
>>   The strictest semantics would be to include the following axiom in
>>   the SKOS scheme: 
>>     skos:broaderGeneric rdfs:subPropertyOf rdfs:subClassOf .
>>
>>   This also mean that subject and object of skos:broaderGeneric are
>>   considered RDF/OWL classes (domain and range of rdfs:subClassOf is
>>   rdfs:Class). This is fine in RDF/OWL Full but not in OWL DL.
>>   Alternatively, we could also just state that it would be reasonable
>>   for application developers to expect this interpretation to be a
>>   correct one.
>>
>> * broaderInstantive
>>
>>   The strictest semantics would be to include the following axiom in
>>   the SKOS scheme: 
>>     skos:broaderInstantive rdf:subPropertyOf rdf:type .
>>
>>   Same discussion as above (in this case only the subject is a
>>   RDF/OWL class).
>> Typical examples:
>>  ex:Asia skos:broaderInstantive ex:Continent .
>>  ex:Rembrandt skos:broaderInstantive ex:Artist
>>
>>
>> Ad 2.
>>
>> a. Subproperties of skos:related:
>>
>> typical examples: artist thesaurus
>>     ex:teacherOf rdfs:subPropertyOf skos:related .
>>   (not symmetric)
>>
>>   ex:workedWith rdfs:subPropertyOf skos:related .
>>   ex:workedWith rdf:type owl:Transitive Property .
>>   (symmetry does not inherit, so needs to be specified explicitly)
>>
>> b. Subproperties of broader/barrower
>>
>> - Use as much as possible the predefined specializations
>>
>> @@ to be extended
>>
>>
>>   
> 

-- 
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Home page: http://www.cs.vu.nl/~guus/
Received on Wednesday, 12 March 2008 15:33:56 GMT

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