Similarity for Conceptual Querying

The focus of this paper is approaches to measuring similarity for application in content-based query evaluation. Rather than only comparing at the level of words, the issue here is conceptual resemblance. The basis is a knowledge base defining major concepts of the domain and may include taxonomic and ontological domain knowledge. The challenge for support of queries in this context is an evaluation principle that on the one hand respects the formation rules for concepts in the concept language and on the other is sufficiently efficient to candidate as a realistic principle for query evaluation. We present and discuss principles where efficiency is obtained by reducing the matching problem which basically is a matter of conceptual reasoning to numerical similarity computation.