12. The computer program product of claim 11 , the program instructions further comprising: program instructions to determine a confidence measure associated with one or more concepts included in the set of evidences, wherein is used as a factor; and program instructions to determine whether to add or remove a given concept included in the first ontology or the residual ontology based at least in part, on the confidence measure associated with that concept.
12. The computer program product of claim 11 , the program instructions further comprising: program instructions to determine a confidence measure associated with one or more concepts included in the set of evidences, wherein is used as a factor; and program instructions to determine whether to add or remove a given concept included in the first ontology or the residual ontology based at least in part, on the confidence measure associated with that concept. 15. The computer program product of claim 12 , the program instructions further comprising: program instructions to perform one or more of the following: (i) compute relatedness of an evidence included in the set of evidences to the old concepts included in the first ontology; (ii) combine relatedness scores of various techniques into a single confidence measure; (iii) determine to expand a knowledge base of a residual ontology based, at least in part, on a type of the evidence included in the set of evidences; and (iv) decay the confidence measure associated with an unused concept that is included in the first ontology.