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Re: Species Concept Mapping RDF fixes and question, should the species be ?represented as a class? Class SpeciesConcept => Class Species Cougar

From: Richard Cyganiak <richard.cyganiak@deri.org>
Date: Fri, 4 Dec 2009 18:58:48 +0000
Cc: Peter DeVries <pete.devries@gmail.com>, public-lod@w3.org, dmozzherin@gmail.com
Message-Id: <3EADFC87-268C-4E2E-9BDD-C65B13AA63F7@deri.org>
To: Antoine Isaac <aisaac@few.vu.nl>
Hi Antoine,

So, can an rdfs:Class also be used as a skos:Concept, or vice versa?

OWL DL folks will obviously not like this, but that's not my problem.

A problem might be this: If there is a skos:Concept, and we use it as  
a class, what exactly are the instances of that class? Having this:

    foo:Cougar a skos:Concept; skos:prefLabel "Cougar".

And then doing this:

    bar:Bob a foo:Cougar .

Then Bob could be an animal, or Bob could be some sort of document,  
because the foo:Cougar concept may have been a "container" for  
documents rather than animals. So the "bar:Bob a foo:Cougar" triple  
really just tells us that bar:Bob is somehow related to or about  
cougars, but not that Bob is an animal of the species Cougar. This  
problem could be solved by saying that "foo:Cougar rdfs:subClassOf  
ex:Animal". So the problem can be worked around. But it still shows  
that using concepts as classes is tricky business.

The other way round -- using classes as concepts -- seems safer. I  
find it hard to find a practical problem with this. Both for classes  
and for concepts there are custom properties for indicating  
equivalence -- owl:equivalentClass and the different skos:match  
properties -- so one can steer clear of owl:sameAs and avoid most of  
the usual coreference problems.

Just random late-night thoughts ...


On 3 Dec 2009, at 18:58, Antoine Isaac wrote:
>>> And in fact, while I understand that it is not very intuitive to  
>>> have Bob the cougar as a skos:Concept (even though it is  
>>> technically allowed), I see less problems for dealing this way  
>>> with the class of cougars...
>> Mentioning that you see less problems without going into any detail  
>> is not exactly useful. I see more problems.
> Yes, I should have been clearer.
> In fact the most important argument (as I understand it from the  
> discussion you started at [1]) against considering a given entity as  
> a skos:Concept is that this entity may not have been designed as  
> part as a knowledge organization endeavour. It is for example rather  
> far-stretched to say that a person like Michelle Obama was conceived  
> as part of a knowledge organization system.
> My point is that this is less problematic for classes, as these are  
> items of a knowledge organization system from the start. They are  
> also "taxonomist business objects", aren't they? So we could easily  
> treat them as skos:Concepts.
> We have in fact touched this aspect in some parts of the SKOS  
> documentation [2,3,4]. I'd be very interested to know whether you  
> think this is wrong view!
> Best,
> Antoine
> [1] http://lists.w3.org/Archives/Public/public-esw-thes/2009Nov/0000.html
> [2] http://www.w3.org/TR/2009/NOTE-skos-primer-20090818/#secskosowl
> [3] http://www.w3.org/TR/skos-reference/#L896
> [4] http://www.w3.org/TR/skos-reference/#L1170
>>> Best,
>>> Antoine
>>>> 2. I'm not sure if it's wise to use the same URI for the Cougar  
>>>> "concept" and the Cougar "class". I don't think that this  
>>>> "punning" is against any spec, but it will cause endless head- 
>>>> scratching among potential users of your data. It would be more  
>>>> straightforward to mint a separate URI for the class, and  
>>>> relating it 1:1 to the species concept using an appropriate  
>>>> property (there's probably one in UMBEL; if not, mint your own --  
>>>> maybe "speciesClass"). Since you own the URI space anyway,  
>>>> minting new URIs would be cheap.
>>>> This kind of punning between concepts, things and classes is an  
>>>> interesting issue, and I'm afraid that it's not yet well  
>>>> understood. Avoiding it puts you on the safe side.
>>>> That being said, can you talk a bit about your motivation for  
>>>> wanting to re-use the same URI?
>>>> Best,
>>>> Richard
>>>>> This should work with OWL2 but I don't know how well it will  
>>>>> work with the
>>>>> LOD.
>>>>> Also I created a VERY preliminary OWL document that would  
>>>>> contain a much
>>>>> more complete representation of the species.
>>>>> My thoughts are that these OWL documents would be used to help  
>>>>> determine
>>>>> what specimens are instances of what species concept.
>>>>> The goal would be to provide an OWL document for those who need  
>>>>> a more
>>>>> complete description of what we mean by the URI, while
>>>>> also providing a much lighter RDF representation that could be  
>>>>> used for
>>>>> concept mapping etc.
>>>>> However, I don't know if I am going about this in the right way.
>>>>> Below are my VERY preliminary examples of what these OWL  
>>>>> documents might
>>>>> look like.
>>>>> The example has some attributes that I thought should be  
>>>>> included in a
>>>>> species document, but it does not have everything that would  
>>>>> like to
>>>>> eventually include.
>>>>> http://rdf.taxonconcept.org/owlses/v6n7p/2009-12-01.owl
>>>>> Doc's at http://rdf.taxonconcept.org/owlses/v6n7p/owl_doc/index.html
>>>>> The common classes etc, would eventually be moved to a separate  
>>>>> ontology
>>>>> that would be imported into each individual species ontology.
>>>>> And these ontologies will need to be fixed so that they work  
>>>>> together, I
>>>>> don't think they do right now.
>>>>> Thanks in Advance, :-)
>>>>> - Pete
>>>>> ----------------------------------------------------------------
>>>>> Pete DeVries
>>>>> Department of Entomology
>>>>> University of Wisconsin - Madison
>>>>> 445 Russell Laboratories
>>>>> 1630 Linden Drive
>>>>> Madison, WI 53706
>>>>> GeoSpecies Knowledge Base
>>>>> About the GeoSpecies Knowledge Base
>>>>> ------------------------------------------------------------

Linked Data Technologist  Linked Data Research Centre
Digital Enterprise Research Institute (DERI), NUI Galway, Ireland
Received on Friday, 4 December 2009 18:59:24 UTC

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