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Re: referencing a concept scheme as the code list of some referrer's property

From: Dave Reynolds <dave.e.reynolds@gmail.com>
Date: Thu, 23 Aug 2012 12:16:55 +0100
Message-ID: <50361127.2090906@gmail.com>
To: Thomas Bandholtz <thomas.bandholtz@innoq.com>
CC: public-esw-thes@w3.org, "<public-lod@w3.org>" <public-lod@w3.org>, sandro@w3.org, Till Schulte-Coerne <till.schulte-coerne@innoq.com>
On 23/08/12 10:22, Thomas Bandholtz wrote:
> Am 23.08.2012 10:40, schrieb Dave Reynolds:
>> [Apologies for continuing the cross-posting]
>>
>> A pattern of using sub-classes of skos:Concept to denote a group of
>> concepts (and thus be able to use rdfs:range in associated ontologies)
>> is a good one. It is recommended best practice in data.gov.uk linked
>> data work, for example.
> Fine. Why then does Data Cube not make use of this?

??

Data Cube certainly *permits* you to use subsets of skos:Concept and to 
declare the rdfs:range of the Dimension and Measure properties, we've 
used this for publishing many environmental data Cubes.

What it doesn't do is *require" you to use this style and only this 
style. It allows you to directly reference the ConceptScheme in keeping 
with SKOS as it is currently used.

>> Having an explicit concept scheme also signals intention.
>
> My notion is that defining subclasses of skos:Concept expresses that you
> want to create a concept scheme.

Not really, it's not an out-of-the-box way of thinking about RDFS/OWL 
but a pattern you could impose on top. In OWL a class is defined by its 
extension (set of values) whereas a ConceptScheme (or whatever you 
replace it by) has an independent existence, it's an individual which 
you want to talk about (for example to say that the scheme is mandated 
by a certain piece of legislation) separate from the enumeration of its 
members.

> Tons of metadata properties (such as skos:pref/altLable or note) do not
> define any expicit domain, so the domain is rdfs:Resource. Why not
> attach them to a rdfs:Class or owl:Class, which are subclasses of
> rdfs:Resource?

Well the relevant properties here are things like skos:topConcept which 
do have domain axioms but if you were changing the specs your could 
certainly remove those.

Assuming domain compatability then in RDFS and OWL/full you are indeed 
free to do this sort of annotation.

In OWL DL there are issues precisely because this is treating a class as 
if it were an individual. OWL 2 eases this with punning (ugh) and 
through the ability to at least declare the range of an 
owl:AnnotationProperty. Whether that easement is enough depends on the 
specifics of your situation, including your tool chain.

You might not personally care about OWL DL but some users of SKOS 
(including Simon, I believe) do have to.

Dave
Received on Thursday, 23 August 2012 11:17:30 UTC

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