W3C home > Mailing lists > Public > public-esw-thes@w3.org > June 2007

Re: [SKOS] central issues

From: Bernard Vatant <bernard.vatant@mondeca.com>
Date: Wed, 27 Jun 2007 14:57:13 +0200
Message-ID: <46825EA9.8010408@mondeca.com>
To: Antoine Isaac <aisaac@few.vu.nl>
Cc: SWD WG <public-swd-wg@w3.org>, public-esw-thes@w3.org

Hi Antoine

Antoine Isaac a écrit :
>>    * Should broader/narrower link concepts of the same concept 
>> scheme, or are they allowed across concept schemes?
>
> Does draft proposal I posted for mapping [1] bring an answer to your 
> question? The idea would be expressing conceptual mapping across 
> concept schemes trying to re-use the existing SKOS semantic 
> relationships when possible ...
Good answers, but not to my question :-) .
My question is about the use of broader/narrower, not of other 
relationships across concept schemes

Let me put it in a more formal way.
Is the following allowed if ex:schemeA and ex:schemeB are different?

ex:foo  skos:inScheme  ex:schemeA
ex:bar  skos:inScheme  ex:schemeB
ex:foo  skos:narrower ex:bar
>>    * If a concept belongs to several concept schemes, would it be 
>> possible / does it make sense to distinguish broader-narrower 
>> hierarchies in different schemes?
>
> I think this is covered by ISSUE-36 ConceptSchemeContainment 
> http://www.w3.org/2006/07/SWD/track/issues/36
Well, it's related, but not exactly covered. The original question of 
Sean is not exactly that one, it aks how to assert the containment of a 
relationship in a ConceptScheme. Mine is to know if an assertion using 
broader-narrower has to be contained in a ConceptScheme at all; Or, it 
implies that the above situation is clarified to begin with. Granted, 
it's not strictly forbidden, but one would think that "a consistent set 
of concepts" implies that broader-narrower are internal. This is what 
one can understand by "consistent" e.g., a thesaurus which is migrated 
to SKOS. Broader-narrower are internal to the Thesaurus.

BTW similar issue can be set for skos:related
>> Related question, I would like to see specified the semantics of 
>> ConceptScheme, and the difference between ConceptScheme and subclass 
>> of Concept.
> ???
OK. It was late last night when I wrote this. There agian, let me be 
more formal.
What are the differences, both semantic and functional, between the 
following modeling choices?

ex:bar      rdf:type      skos:ConceptScheme
ex: foo  skos:inScheme   ex:bar

vs

ex:bar       rdfs:subClassOf      skos:Concept
ex: foo  rdf:type   ex:bar

IOW, in which cases do I need a Concept Scheme rather than a subclass of 
skos:Concept. This is one of the most obscure points of the current 
spec, as far as I am concerned.

Is it clearer now?

Bernard
>
> Cheers,
>
> Antoine
>
> [1] 
> http://www.w3.org/2006/07/SWD/wiki/SkosDesign/ConceptualMapping/ProposalOne 
>
>>
>> Bernard
>>> Hi all,
>>>
>>> I'd like to suggest we focus some attention on several issues to do 
>>> with the central stuff in SKOS, like the skos:Concept class, the 
>>> SKOS labelling properties and the SKOS semantic relation properties.
>>> This would help us to fill out some of the earlier parts of the SKOS 
>>> Semantics wiki draft [1]. The wiki draft has only one section so 
>>> far, on grouping constructs, and so looks a bit empty :) This would 
>>> also help the discussion of other issues, such as the relationships 
>>> between labels.
>>>
>>> There are three central issues in the tracker we could look at:
>>>
>>>  * [ISSUE-31] "BasicLexicalLabelSemantics" - defining the semantics 
>>> of the three basic labelling properties, skos:prefLabel, 
>>> skos:altLabel and skos:hiddenLabel
>>>  * [ISSUE-44] "BroaderNarrowerSemantics" - defining the semantics of 
>>> skos:broader and skos:narrower
>>>  * [ISSUE-54] "ConceptSemantics" - defining the semantics of 
>>> skos:Concept
>>> Issue 31 is already open. Issues 44 and 54 need to be opened (I just 
>>> raised 54).
>>>
>>> Of course we should also continue the very valuable discussion of 
>>> other issues and work to our requirements document!
>>>
>>> Cheers,
>>>
>>> Alistair.
>>>
>>> [1] <http://www.w3.org/2006/07/SWD/wiki/SKOS/Semantics>
>>> [ISSUE-31] <http://www.w3.org/2006/07/SWD/track/issues/31>
>>> [ISSUE-44] <http://www.w3.org/2006/07/SWD/track/issues/44>
>>> [ISSUE-54] <http://www.w3.org/2006/07/SWD/track/issues/54>
>>>
>>> -- 
>>> Alistair Miles
>>> Research Associate
>>> Science and Technology Facilities Council
>>> Rutherford Appleton Laboratory
>>> Harwell Science and Innovation Campus
>>> Didcot
>>> Oxfordshire OX11 0QX
>>> United Kingdom
>>> Web: http://purl.org/net/aliman
>>> Email: a.j.miles@rl.ac.uk
>>> Tel: +44 (0)1235 445440
>>>
>>>   
>>
>
>
>

-- 

*Bernard Vatant
*Knowledge Engineering
----------------------------------------------------
*Mondeca**
*3, cité Nollez 75018 Paris France
Web:    www.mondeca.com <http://www.mondeca.com>
----------------------------------------------------
Tel:       +33 (0) 871 488 459
Mail:     bernard.vatant@mondeca.com <mailto:bernard.vatant@mondeca.com>
Blog:    Leçons de Choses <http://mondeca.wordpress.com/>
Received on Wednesday, 27 June 2007 12:57:34 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:38:58 GMT