UNION: An Unreferenced Metric for Evaluating Open-ended Story Generation Jian Guan author Minlie Huang author 2020-11 text Proceedings of the 2020 Conference on Empirical Methods in Natural Language Processing (EMNLP) Bonnie Webber editor Trevor Cohn editor Yulan He editor Yang Liu editor Association for Computational Linguistics Online conference publication guan-huang-2020-union 10.18653/v1/2020.emnlp-main.736 https://aclanthology.org/2020.emnlp-main.736/ 2020-11 9157 9166