Re: Astounding silence about same-ness Re: Concept Equivalence, IFPs, skos:subjectIndicator and owl:sameAs

Hi Stuart
> Hello Bernard,
>
> Thanks for breaking the silence :-) I was beginning to wonder whether my
> email had fallen into a blackhole.
>   
There is no black hole for questions. They are like water, they can 
travel a long way underground, and reappear at most unlikely time and place.
>
> I followed your reference [1] and like the bnode idea that you present.
> However, I think that it works mostly because dc:subject is not an IFP,
> rather than because the object nodes are blank - if dc:subject were an
> IFP we'd have the same problem whether or not the object nodes were
> blank.
>   
Yes of course. But the main point of the blank node is to stop the 
recursivity of references.
> As an aside, I was quite surprise to find Bretange reduced to a single
> point without geographic extent!
>
> 	from: http://sws.geonames.org/3030293/ 
> 	<wgs84_pos:lat>48.0</wgs84_pos:lat>
> 	<wgs84_pos:long>-3.0</wgs84_pos:long> 
>   
I'm not completely happy with that myself, wondering how all my 
ancestors made up their living in such a narrow place. But this is how 
geonames data base was built so far. A feature = a pin on a map. Same 
issue for rivers, and even cities. Hopefully this will evolve into 
something more subtle over time.
>
> I'll profess complete ignorance on Topic Maps... but if things are as
> you say, then presumably either: a topic can have no more than one
> subject 
>   
That's exactly so : a topic represents exactly one subject, two topics 
with the same subject should be merged.
> or two topics with multiple subject that have at least one subject in
> common must (necessarily) have all subjects in common!.
>   
Topics can't have multiple subjects, but they can have multiple subject 
indicators (which all indicate the same subject).
> I guess that much hinges on distinctions between what constitutes a
> tm:Subject, a tm:Topic and a skos:Concept.
>   
Indeed
>
> With skos:subjectIndicator being an IFP:
>
> [I be guilty of skos abuse here - I don't know if our respective
> vacations are legitimate as skos:Concepts]
>
> :stuartVacation2006
> 	a				skos:Concept;
> 	skos:subjectIndicator	ex:YukonTerritory;
> 	skos:subjectIndicator	ex:VancouverBC;
> 	skos:subjectIndicator	ex:Canada;
> 	skos:subjectIndicator	ex:SummerVacation.
>   
I think this is a completely incorrect use of subjectIndicator. A 
subject indicator is not another concept, as it seems to be in your 
examples. For :stuartVacation2006 it would be some resource making 
explicit for humans what you mean by that concept, e.g. some Web page 
where you expose where, when, how you took vacations in 2006. Maybe this 
resource itself would have the other concepts as dc:subject.
> :bernardVacation2006
> 	a				skos:Concept;
> 	skos:subjectIndicator	ex:<SomewhereElse>;
> 	skos:subjectIndicator	ex:SummerVacation.
>
> the concepts of our respective summer vacations become one and the same,
>   
It's not the case if we both use proper subject indicators are explained 
above. My Web page will not be yours, and the concepts will keep distinct.

The real use case would be that we have both similar concepts of 
vacation in our vocabulary, and to know how to express that they attempt 
to conceptualize the same thing
and we have used each a subject indicator in our own language

stuart:Vacation     skos:subjectIndicator       
http://en.wikipedia.org/wiki/Vacation
bernard:Vacances   skos:subjectIndicator    
http://fr.wikipedia.org/wiki/Vacances

... and back to the primitive issue
> I strikes me that making skos:subjectIndicator an IFP is probably a
> mistake. Removing that assertion would certainly remove the potential to
> construe unintended equivalences.
>   
I agree.
> I think I should try to understand Topic Maps (an merging of Topic Maps)
> a bit better.
>   
Good luck :-)

Bernard

-- 

*Bernard Vatant
*Knowledge Engineering
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*Mondeca**
*3, cité Nollez 75018 Paris France
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Mail:     bernard.vatant@mondeca.com <mailto:bernard.vatant@mondeca.com>
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Received on Tuesday, 7 November 2006 17:12:55 UTC