In MBRAR, we replace the loss function with the gain function that measure the correlation between answer candidates.
the objective of the MBRAR approach for single QA system is to find the answer candidate that is most supported by other candidates under QA system's distribution, which can be formally written as: denotes the hypothesis distribution estimated on the search space H(Q) based on the following log-linear formulation: is the posterior probability of the answer candidate A k based on QA system's ranking model, β is a scaling factor which controls the distribution P (•) sharp (when β > 1) or smooth (when β < 1).