Re: Drilling into the LOD Cloud

On 28 Sep 2008, at 19:01, Kingsley Idehen wrote:

>
> Dan Brickley wrote:
>> Kingsley Idehen wrote:
>>>
>>> Then between UMBEL and OpenCyc:
>>>
>>> 1. owl:sameAs
>>> 2. owl:equivalentClass
>>
>> If these thingies are owl:sameAs, then presumably they have same IP- 
>> related characteristics, owners, creation dates etc?
>>
>> Does that mean Cycorp owns UMBEL?
> Dan,
>
> No, it implies that in the UMBEL data space you have equivalence  
> between Classes used to define UMBEL subject concepts (subject  
> matter entities) and OpenCyc.

I think Dan's point is that owl:sameAs is a very strong statement, as  
illustrated by the ownership question. If opencyc:Motorcyle  
owl:equivalentClass umbel:Motorcycle then they have the same  
extension. Informally, any use you make of one as a class can be  
replaced by the other without changing the meaning of the whole.  
However if the are owl:sameAs they name the same thing, so  
dc:creationDate, dc:creator, cc:license, rdfs:isDefinedBy etc etc are  
the same for each, which strike me as unhelpful side effects.  
owl:equivalentClass is the vocabulary mappers' friend :-)

Damian

Received on Sunday, 28 September 2008 21:32:53 UTC