Re: [DBpedia-discussion] Call for Ontology Editor demos for DBpedia

On 07/06/2017 11:56 AM, Sebastian Samaruga wrote:
> Question: isn't it possible to 'aggregate' classes of subjects in respect to
> the properties / predicates some set of subjects have in common. Example: a
> Person class subjects would have 'birthPlace', 'birthDate' and 'name'
> properties and an Artist subclass would have those properties of Person plus
> 'creatorOf' properties of artworks objects. So a superclass would have a
> superset of the properties of a subclass.
> 
> Sorry for my ignorance. Best,
> Sebastian.


It is always possible to replace classes by properties.  For each class set up
a boolean property that signals membership in the class.   This is not a good
idea in all cases, though.

It is sometimes possible to replace classes by commonalities in other data.
For example, person born in the seventeenth century can be those people whose
birthdate is in the seventeenth century.   This does depend on the other data
being complete in some sense.  Sometimes, however, this is not possible.  What
makes an animal a person, for example?  From here we get the notion of natural
kinds.

So maybe artist can be replaced by those people who have created some artwork,
except that then I want to claim that some person is an artist without
providing the artwork.   Maybe I can make this claim (exists produced artwork
in OWL, for example) but maybe the underlying representation language can't
state it (primeness of numbers for example).

By the way, superclasses would have a subset of the properties of their
subclasses, not a superset.

Peter F. Patel-Schneider
Nuance Communications

Received on Friday, 14 July 2017 17:35:03 UTC