Rich semantics and expressiveness

Hi all,

A question from someone who is not well-read in the knowledge  
representation literature. What is meant by statements such as this:

     "In general, ontologies are more expressive and have richer
      semantics than relational schemas ..." [1]

Are there definitions for "expressivity" and "semantic richness"? Is  
there an objective measurement for these dimensions?

Cheers,
Richard

[1] http://www.cs.uoregon.edu/~paea/research/ssws06.pdf

Received on Wednesday, 21 February 2007 15:06:42 UTC