RE: Comment: ISSUE-70

Hi Sean!
    You're correct:  if each is a subset of the other, they are
identical.

  So, if skos:broader is supposed to represent something more general
than a set or subset, could you please give examples to support what
that could be, to which this subset reasoning would not apply?

Thank you!

Jody DeRidder
Digital Library Center
University of Tennessee Libraries
Knoxville, Tennessee

-----Original Message-----
From: Sean Bechhofer [mailto:sean.bechhofer@manchester.ac.uk] 
Sent: Tuesday, February 12, 2008 9:40 AM
To: Deridder, Jody L
Cc: public-swd-wg@w3.org
Subject: Re: Comment: ISSUE-70


On 11 Feb 2008, at 02:10, Deridder, Jody L wrote:

> This is related to Issue-69.
>
> <A> skos: broader <B> .
> <B> skos: broader <A>.
>
> is again, nonsense.  If B is a subset of A, then A cannot be a  
> subset of B.  skos:broaderTransitive needs to be defined as an  
> irreflexive property.

Jody

I think it's a little strong to say this is "nonsense". The  
skos:broader relationship is *not* the same as subset. If B is a  
subset of A, then A can certainly be a subset of B -- if it is, then  
it's simply the case that the two sets are identical. However,  
skos:broader is intended to represent something more general, and in  
some ways less "formal" than subset (we already have rdfs:subClassOf  
to represent the subclass relationship). So we should be careful not  
to conflate the two.

Having said that, it may be the case that it is appropriate to define  
skos:broader as ireflexive, but that would be quite a strong  
restriction.

	Sean

--
Sean Bechhofer
School of Computer Science
University of Manchester
sean.bechhofer@manchester.ac.uk
http://www.cs.manchester.ac.uk/people/bechhofer

Received on Tuesday, 12 February 2008 16:46:09 UTC