Re: Defining cross products in OWL-1.1

From: Ulrike Sattler <sattler@cs.man.ac.uk>
Subject: Re: Defining cross products in OWL-1.1
Date: Fri, 12 Oct 2007 14:00:09 +0100

> On 12 Oct 2007, at 12:14, Michael Schneider wrote:

[...]

> >   A similar definition would be
> >      brother = sibling INTERSECTION range(Male)
> >   using range(x) as a shorthand for crossProduct(owl:Thing,x)

> this is a confusing shorthand:
> 
> - if a property p has range X, say Male, then, whenever we find a  
> tuple (a,b) in p, we know that b must be an instance of X. Eg,  
> whenever a has a brother b, then b must be Male.
> 
> - if we would say that p is the crossproduct between Y and X, then,  
> given any two instances y of Y and x of X, we know that (y,x) are in  
> p. This is very different from the above point.


Oops, yeah.  Sorry about that.

I meant the latter.

peter

Received on Friday, 12 October 2007 14:14:03 UTC