WikiQA: A Challenge Dataset for Open-Domain Question Answering Yi Yang author Wen-tau Yih author Christopher Meek author 2015-09 text Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing Lluís Màrquez editor Chris Callison-Burch editor Jian Su editor Association for Computational Linguistics Lisbon, Portugal conference publication yang-etal-2015-wikiqa 10.18653/v1/D15-1237 https://aclanthology.org/D15-1237/ 2015-09 2013 2018