DAML+OIL model theory stance on classes as instances

• Previous message: Ian Horrocks: "DQL queries"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] [ attachment ]
• Mail actions: [ respond to this message ] [ mail a new topic ]

As there was some discussion yesterday about whether classes had properties
in the DAML+OIL model theory, I reread the model theory document to see
exactly what it said.

The result - a definite no, shading to maybe.  :-)


The model theory has three mappings, each of which map the nodes of a
collection of RDF triples into something else
	IC, which maps classes (nodes) to their extensions
	IR, which maps relationships (nodes) to their extensions, which are
	    (roughly) 2-place relationships over the domain of discourse
	IO, which (roughly) maps individuals (nodes) to their extensions,
	    which are (roughly) elements of the domain of discourse

So classes are nodes in the RDF graph, and do not participate in the
extension of relationships, which interrelate things in the domain of
discourse.

However, IO maps nodes into the domain of discourse.  Thus the IO mapping
of classes do participate in the extensions of relationships, leading to
the ``maybe'' shading.


peter

• Next message: Richard Fikes: "Apology to the Authors of the DAML+OIL Model-Theoretic Semantics"
• Previous message: Ian Horrocks: "DQL queries"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] [ attachment ]
• Mail actions: [ respond to this message ] [ mail a new topic ]

This archive was generated by hypermail 2.1.4 : 07/10/02 EDT