Compared with RKN, which only uses the paragraph-question relevance, our completed ranker can further utilize the paragraph-paragraph relevance to aggregate the evidence among relevant paragraphs, thereby increasing their confidence scores.
given the paragraph probabilities Pr sen ∈ R n , the ranker is trained by minimizing the loss: For the reader, we first select k paragraphs based on the RS→WS strategy and then obtain the final scores Pr s i and Pr e i for each paragraph, where Pr s i (t)/Pr e i (t) represent the start/end scores of the t-th word in the i-th paragraph.