4. The method of claim 3 , wherein the first case and the second case are further classified based on each of: (i) metadata describing an attribute of a user presenting the respective case to the question answering system, (ii) a content of a question in the respective case, and (iii) a type of the question in the respective case, wherein the metadata is received with the first case.
4. The method of claim 3 , wherein the first case and the second case are further classified based on each of: (i) metadata describing an attribute of a user presenting the respective case to the question answering system, (ii) a content of a question in the respective case, and (iii) a type of the question in the respective case, wherein the metadata is received with the first case. 5. The method of claim 4 , wherein the attribute comprises: (i) a role of the user, (ii) an affiliation of the user, (iii) an expertise of the user, and (iv) a set of predefined preferences of the user.