6. The method of claim 1 , wherein the comparing includes determining a degree of similarity between a user-specific ontology of the one or more user-specific ontologies and the plurality of defined ontologies.
6. The method of claim 1 , wherein the comparing includes determining a degree of similarity between a user-specific ontology of the one or more user-specific ontologies and the plurality of defined ontologies. 7. The method of claim 6 , further including: selecting a defined ontology of the plurality of ontologies having the highest degree of similarity to the user-specific ontology; and determining a category corresponding to the selected defined ontology, wherein the categorizing the user includes categorizing the user as a member of the determined category.