Recent work on learning to rank (L2R) has shown that deep learning and kernel methods are two very effective approaches, given their ability of engineering features.
in question answering (QA), Convolutional Neural Networks (CNN), e.g., (Severyn and Moschitti, 2015;Miao et al., 2016;Yin et al., 2016) can automatically learn the representation of question and answer passage (Q/AP) in terms of word embeddings and their non-linear transformations.