Non-Factoid Japanese Question Answering through Passage Retrieval that Is Weighted Based on Types of Answers Masaki Murata author Sachiyo Tsukawaki author Toshiyuki Kanamaru author Qing Ma author Hitoshi Isahara author 2008 text Proceedings of the Third International Joint Conference on Natural Language Processing: Volume-II conference publication murata-etal-2008-non https://aclanthology.org/I08-2100/ 2008