2. The method of claim 1 , the method further comprising: the computer determining a confidence measure associated with one or more concepts included in the set of evidences, wherein is used as a factor; and the computer determining 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.
2. The method of claim 1 , the method further comprising: the computer determining a confidence measure associated with one or more concepts included in the set of evidences, wherein is used as a factor; and the computer determining 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. 5. The method of claim 2 , the method further comprising: the computer performing one or more of the following: (i) computing relatedness of an evidence included in the set of evidences to the old concepts included in the first ontology; (ii) combining relatedness scores of various techniques into a single confidence measure; (iii) determining 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) decaying the confidence measure associated with an unused concept that is included in the first ontology.