28. A computer-readable medium having stored thereon a set of instructions which when executed perform a method for recommending an item to a user, the method, comprising: selecting, based on preferences of the user, an ontology from a set of predefined ontologies; wherein, the ontology includes as nodes in a graph that represent concepts, the nodes including a scored node and an unscored node, the scored node having an associated score that is specific to the user; determining a personalized score of the unscored node in the ontology using the associated score for the scored node and a structural relationship of the unscored node with the scored node in the graph; identifying, for the user, a qualifying concept horn the concepts in the ontology for which the personalized scores have been computed, wherein, the qualifying concept having a qualifying score among the personalized scores computed for the concepts at the nodes of the ontology; wherein, the qualifying concept is used to select the item to be recommended to the user.
28. A computer-readable medium having stored thereon a set of instructions which when executed perform a method for recommending an item to a user, the method, comprising: selecting, based on preferences of the user, an ontology from a set of predefined ontologies; wherein, the ontology includes as nodes in a graph that represent concepts, the nodes including a scored node and an unscored node, the scored node having an associated score that is specific to the user; determining a personalized score of the unscored node in the ontology using the associated score for the scored node and a structural relationship of the unscored node with the scored node in the graph; identifying, for the user, a qualifying concept horn the concepts in the ontology for which the personalized scores have been computed, wherein, the qualifying concept having a qualifying score among the personalized scores computed for the concepts at the nodes of the ontology; wherein, the qualifying concept is used to select the item to be recommended to the user. 29. The method of claim 28 , further comprising, recommending the item to the user.