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Re: [ISSUE-77] [ISSUE-48] Re: [Dbpedia-discussion] Skos subject properties are deprecated

From: Richard Cyganiak <richard@cyganiak.de>
Date: Thu, 24 Jan 2008 13:24:12 +0000
Cc: Peter Ansell <ansell.peter@gmail.com>, dbpedia-discussion@lists.sourceforge.net, SKOS <public-esw-thes@w3.org>
Message-Id: <FC67144C-AD84-4ED6-AA3E-AAF8C4640290@cyganiak.de>
To: Bernard Vatant <bernard.vatant@mondeca.com>

All,

I agree with Bernard that SKOS needs a property for attaching  
resources to concepts.

The problem with skos:subject at the moment is this: The Core Guide  
gives the impression that the domain of skos:subject is documents  
only. But there is no explicit domain declared in the vocabulary  
definition. Furthermore, several parties (e.g. DBpedia) have a clear  
need for a property that relates non-document resources to  
skos:Concepts.

I think there are three options for resolving this:

A) Clarify that the domain of skos:subject is indeed any resource, and  
that the term “subject” is used loosely here.

B) Clarify that the domain of skos:subject is documents only, and  
introduce a new super-property of skos:subject that explicitly covers  
any resource. It could be named for example skos:category, or  
skos:indexedAs.

C) Clarify that the domain of skos:subject is documents only, and  
leave the task of defining a property non-document resources to others.

My preference would be, in that order, B), A), C).

Thanks,
Richard


On 24 Jan 2008, at 12:45, Bernard Vatant wrote:

> Hello all
>
> Some precisions before anyone gets carried away :-)
> The latest SKOS draft Peter mentions is certainly the editor's draft  
> at
> http://www.w3.org/2006/07/SWD/SKOS/reference/20080118
> This is only an editor's draft and has no official status whatsoever
> The skos:subject property is mentioned as "at risk", which means its  
> relevancy is questioned. It's not *deprecated* so far AFAIK, but  
> under discussion.
> There are two related "open issues" on this
> http://www.w3.org/2006/07/SWD/track/issues/77
> http://www.w3.org/2006/07/SWD/track/issues/48 <http://www.w3.org/2006/07/SWD/track/issues/77 
> >
>
> I take, as Antoine (Isaac), that the later is a generalization of  
> the former :
> "The SKOS model should contain mechanisms to attach a given resource  
> (e.g. corresponding to a document) to a concept the resource is  
> about, e.g. to query for the resources described by a given concept."
>
> I think this is obvious. Otherwise what is the point of SKOS  
> altogether? The property skos:subject was (and still is) candidate  
> to support this mechanism. As has been pointed in e.g., the other  
> ongoing thread on dbpedia list [1], the term "subject" can appear to  
> be too specific in meaning to cover all cases of linking  a resource  
> to a concept, and strange in some borderline cases. But it's more a  
> question of terminology than a question of need of such a generic  
> property. In the referenced thread, I think the criticism should be  
> more interpreted as a weird construction of Wikipedia categories  
> (some are very weird indeed) than as a mistake in using skos:subject  
> in DBpedia to represent the Wikipedia categorisation.
>
> My take on this is that such a generic property is needed and should  
> not be deprecated. Since a lot of people (including dbpedia folks,  
> but not only) have started using skos:subject in the above quoted  
> very generic sense, and I think they are OK to do so, it should be  
> kept as is. But it should be put in best practices that whenever you  
> want to specify an indexing property, you define a specific  
> subproperty of skos:subject.
>
> SKOS specification should stress and explain what the *functional*  
> semantics of this property are, and are not. Simply to *retrieve  
> resources* indexed on a concept. Not to infer any specific semantics  
> on the indexing link. Just : "If you are interested in this concept,  
> here are resources dealing about it in some way". No more, no less.  
> If you want to be more specific, use a specific subproperty.
>
> Bernard
>
>
> [1] http://sourceforge.net/mailarchive/forum.php?thread_name=834575810801231916m4729f854lf34f47fe9af0a746%40mail.gmail.com&forum_name=dbpedia-discussion
>
>
>
> Richard Cyganiak a écrit :
>> Peter,
>>
>> On 24 Jan 2008, at 05:41, Peter Ansell wrote:
>>
>>> I am new to this list, but in a discussion on another list we were
>>> discussing the use of the skos:subject and related items, something
>>> which dbpedia has invested in heavily to represent the wikipedia
>>> category system.
>>>
>>> The latest SKOS draft has deprecated these properties.
>>>
>>
>> Can you give us some background on this decision? I have a hard  
>> time  understanding why this step was taken.
>>
>>
>>> What will dbpedia use instead?
>>>
>>
>> I don't know. Do you have any suggestions?
>>
>> Richard
>>
>>
>>
>
> -- 
>
> *Bernard Vatant
> *Knowledge Engineering
> ----------------------------------------------------
> *Mondeca**
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> Web:    www.mondeca.com <http://www.mondeca.com>
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> Mail:     bernard.vatant@mondeca.com <mailto:bernard.vatant@mondeca.com 
> >
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>
>
Received on Thursday, 24 January 2008 13:24:29 GMT

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