9. The computer system of claim 6 wherein the classification synthesis component defines dimensional concept relationships for concept definitions if the attributes of the respective concept definitions are related, directly or indirectly, as defined by the facet attribute hierarchy thereby to infer explicit relationships.
6. The computer system of claim 1 comprising a classification synthesis component for building dimensional concept taxonomies, said synthesis component defining the concept definitions and expressing the dimensional concept relationships between the concepts for the domain to be classified in accordance with the faceted data set.