3. The method of claim 2 , wherein the justifying passage score for each of the candidate passages and the answer score are final scores, and further comprising: producing one or more algebraic formulas indicating how each of the final scores was computed based on relation match features of the matching.
4. The method of claim 3 , further comprising: finding assignments of a plurality of relation weights to the relation match features that minimize a loss function on the final scores with respect to the candidate answer.