1. A computer program product, comprising: a non-transitory computer-readable storage medium having computer-readable program code embodied therewith, the computer-readable program code comprising: computer-readable program code configured to compute a concept score for a first concept in a first case, wherein the concept score is based on whether the first concept is present in at least one of a candidate answer and an item of supporting evidence; computer-readable program code configured to adjust the concept score based on a coefficient for the first concept in a machine learning concept model for the first concept, wherein the coefficient reflects a relevance of the first concept in generating a correct response to the first case; computer-readable program code configured to exclude the first concept from consideration when analyzing the candidate answer and the item of supporting evidence to generate a response to the first case upon determining at least one of: (i) that the adjusted concept score does not exceed a predefined minimum weight threshold and (ii) that the coefficient does not exceed a predefined noise threshold; and computer-readable program code configured to consider the first concept when analyzing the candidate answer and the item of supporting evidence to generate the response to the first case upon determining at least one of the concept score and the coefficient exceeds a predefined maximum weight threshold.