This experiment considers correspondences between (1) the classes (i.e., opinion or fact) assigned by the subjectivity filters to the sentences containing answers, and (2) the classes of the questions the answers are responses to (according to the OpQA annotations).
we compute the probabilities (where ans = answer): P(ans is in a C1 sentence | ans is the answer to a C2 question) for all four combinations of C1=opinion, fact and C2=opinion, fact.