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Re: SKOS ISSUE-39: clarification?

From: Antoine Isaac <aisaac@few.vu.nl>
Date: Tue, 04 Dec 2007 16:21:38 +0100
Message-ID: <47557082.0@few.vu.nl>
To: Emma McCulloch <e.mcculloch@strath.ac.uk>
CC: SKOS <public-esw-thes@w3.org>, SWD WG <public-swd-wg@w3.org>

Hi Emma,

Thanks for the quick feedback!
Actually the fact that some application were rather looking at thesaurus 
terms was also a reason for introducing skos:relatedMatch, because 
overlappingMatch is very much resource-oriented (even though I do think 
it is useful for many cases).
If you find examples, these would be highly welcome. As already said, my 
proposal is to be discussed. If the community thinks that one of 
overlappingMatch or relatedMatch should be dropped, then let it be that 
way...

Cheers,

Antoine

> Hi Antoine,
>  
> Many thanks for your reply; it has definitely cleared a few things up for me.
>  
> I totally agree with the proposed deprecation of major and minorMatch. We found it particulary difficult to come up with an example of what might constitute a minorMatch and the division at the 50% point was extremely difficult to gague, as you say. I also agree that overlappingMatch is a valuable mapping type and will be far more straightforward to apply. I think we're finding the application of the mapping vocab quite difficult in HILT generally, since SKOS is geared towards equivalence between indexed resources, whereas we are looking purely at thesaurus terms with no attachment to actual resources.
>  
> The platypus/egg example has made things clearer (as has your France/War example) but I believe there will be instances where the distinction between related and overlapping might be more blurred. I'm not absolutely convinced that they are sufficiently distinct if both are to be used in inter thesaurus mapping. I'll try to find some examples of this in our ongoing mapping work.
>  
> Thanks again, your response is much appreciated,
> Emma
>
> ________________________________
>
> From: public-esw-thes-request@w3.org on behalf of Antoine Isaac
> Sent: Mon 03/12/2007 21:45
> To: SKOS; Emma McCulloch
> Cc: SWD WG
> Subject: Re: SKOS ISSUE-39: clarification?
>
>
>
>
> Dear Emma,
>
> I'm very glad to have some comments by someone from HILT! I will try to
> answer your questions below:
>   
>> 1)       What is the status of this issue and proposal (ISSUE-39)?
>>
>>     
>
> The issue states that there is a requirement for SKOS (i.e. conceptual
> mapping links) that is not dealt with in the current version of SKOS.
> And [1] is a proposal to tackle this issue, by having the SKOS namespace
> featuring some constructs devoted to mapping representation. Even if
> SKOS mapping (I'll keep the MVS you use for it) is around, it is not
> stable and has no official W3C status.
> Notice that for the moment [1] has no official status either, it's just
> a proposal to be discussed. Your comments/questions are therefore highly
> welcome.
>
>   
>> 2)       ISSUE-39 states that Major/minorMatch are deprecated, along with
>> classes AND, OR and NOT. It also 'transfers' skos:mappingRelation,
>> skos:exactMatch; skos:broadMatch and skos:narrowMatch from the MVS
>> into the
>> standard SKOS vocabulary. Does this mean that the MVS will no longer
>> be used
>> if this proposal is accepted?
>>
>>     
>
> Yes, the current proposal states that MVS would not exist as such any
> more. Some of its elements would be purely deprecated (major/minorMatch)
> while some other would be technically deprecated but in practice moved
> to the 'official' SKOS namespace. the latter case would be true for the
> mappingRelations, but also perhaps for AND/OR/NOT. The resolution for
> the last elements would wait till a resolution for another issue,
> ISSUE-40 [2]
> Notice again that this is a proposal, which can be adjusted. For
> example, even if people agree on removing major/minorMatch, there could
> be a consensus on keeping the official mapping vocabulary in the same
> separate namespace that is used now (http://www.w3.org/2004/02/skos/mapping)
>
>   
>> 3)       skos:relatedMatch and skos:overlappingMatch are introduced: could
>> you please provide a definition of relatedMatch (assuming this is for
>> inter-thesaurus mapping) and perhaps an example? I'm not clear of the
>> distinction between this and overlappingMatch, at a practical level.
>>
>>     
>
> Before answering this question: is the platypus/egg example in [1] not
> clear enough? If yes, please say so, and I'll try to find another one...
>
> That being said, the difference between relatedMatch and
> overlappingMatch is not 100% obvious even to me.
> The main motivation is that the previous SKOS mapping specification was
> assuming a quite 'mechanical', extensional approach to partial mappings.
> minor/majorMatch were defined on the basis that resources were described
> by both mapped concepts.
> If I wanted to remove minor/majorMatch (because I find the 50% criterion
> too much arbitrary), I had to find something with the same kind of
> criterion to replace them (because I thought there was some point in
> representing this "overlapping extensions" situations). So
> overlappingMatch is defined as a relation that holds when there is a set
> of documents potentially described by the two concepts at the same time.
> The problem is that this does not render the associative "related" link
> between terms from a thesaurus. Imagine two concepts, "France" and
> "War", coming from two thesauri. In a library, there will be an overlap
> between the sets of books indexed by the two concepts. Yet, I dare not
> imagine that there would be a "related" link between the two concepts,
> if they stood withing one single thesaurus. If a searcher is interested
> in resources about "France", you will not generally try to point him to
> resources about War. In my opinion, this is a case where you would have
> an overlapingMatch but no relatedMatch.
> Does this make enough sense? (please do not hesitate to say if you are
> not fully convinced)
>
>   
>> 4)       The first version of ISSUE-39 proposed to introduce
>> skos:equivalentConcept as a replacement for skosm:exactMatch - has
>> this idea
>> now been dropped?
>>
>>     
>
> Yes. The first proposal tried to deprecate the current MVS as much as
> possible, and to have it replaced it by the exsiting SKOS semantic
> relations (broader, related, narrower, but there is no equivalence link
> until now in this part of SKOS). Given that this proposal has not been
> very popular, I took the inverse stance, which is to keep mapping links
> distinct from semantic relations. I thought that in this case it would
> be better to stay as close as possible to the MVS elements.
>
> Best regards,
>
> Antoine
>
> [1]
> http://www.w3.org/2006/07/SWD/wiki/SkosDesign/ConceptualMapping/ProposalTwo
> [2] http://www.w3.org/2006/07/SWD/track/issues/40
>
>
>
>
>   
Received on Tuesday, 4 December 2007 15:23:29 GMT

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