NON-FACTOID QUESTION ANSWERING SYSTEM AND COMPUTER PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a non-factoid question answering system which can offer better accuracy.SOLUTION: A question answering system 160 includes; a candidate sentence retrieval unit 222 which takes out answer candidates from a corpus storage unit 178 in response to a question; a feature vector generator unit 232 which generates a feature for the combination of the question and each of the answer candidates; an SVM 176 which has learned to calculate a score representing a degree of correctness of the combination of the original question and the answer candidate when the feature vector is given; and an answer sentence ranking unit 234 which outputs as an answer the answer candidate having the highest calculated score. The feature is generated based on results of a morphological analysis and a syntax analysis for the question, positively or negatively evaluated phrases in the question and polarity thereof, and semantic classes of nouns in the feature.