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Re: How to distinguish unique and non-unique prefLabels?

From: Jakob Voss <jakob.voss@gbv.de>
Date: Wed, 12 Jan 2011 17:43:15 +0100
Message-ID: <4D2DDA23.1010006@gbv.de>
CC: "public-esw-thes@w3.org" <public-esw-thes@w3.org>
Hi Ford,

You wrote:

> The solution you proposed - defining skos:uniquePrefLabel
> rdfs:subPropertyOf skos:prefLabel - might result in an integrity
> violation after inferencing.  Based on the example you provided, and
> please correct me if I'm wrong, you could end up with two
> same-language skos:prefLabels for the same resource after
> inferencing.  This would violate the skos:prefLabel integrity
> condition that "a resource has no more than one value of
> skos:prefLabel per language tag."[1]

You are right - if it violates the condition, the solution is not a 
valid solution.

> The only other thing I could think to do would be to add a "no
> linguistic content" language designation ("zxx") to the second,
> "unique", to-be-used-with-the-KOS-as-thesaurus skos:prefLabel
> property (I'm proposing this, but can't say that I'm sold on the idea
> myself).  This would permit the two labels to peaceably coexist as
> skos:prefLabel properties.  At best, this keeps the information in
> the skos namespace, but still fails to lend any meaningful
> distinction to your "unique" prefLabel.  You'd still have to define a
> system rule that says "when using the KOS as a thesaurus, look for
> the 'zxx' prefLabel," but this solution would unambiguously identify
> a concept within a KOS and its applications.

Yes, 'zxx' is not very intuitive. At the moment I think that the best 
solution is to use skos:prefLabel unique, but some concept schemes will 
not have preferred labels, so there is a skos:Concept without this 
property. Instead you could add rdfs:label, but then the application 
does not know which rdfs:label to use as the main heading. As dc:title 
is also a sub-property of rdfs:label, we could use dc:title instead. But 
I am not comfortable with creating unique labels, if the scheme just 
does not have unique labels. SKOS applications should be able to deal 
with concepts that have no skos:prefLabel and with schemes that have 
non-unique skos:prefLabels.

Jakob

-- 
Jakob Vo▀ <jakob.voss@gbv.de>, skype: nichtich
Verbundzentrale des GBV (VZG) / Common Library Network
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Received on Wednesday, 12 January 2011 16:44:02 UTC

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