Word-level Textual Adversarial Attacking as Combinatorial Optimization Yuan Zang author Fanchao Qi author Chenghao Yang author Zhiyuan Liu author Meng Zhang author Qun Liu author Maosong Sun author 2020-07 text Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics Dan Jurafsky editor Joyce Chai editor Natalie Schluter editor Joel Tetreault editor Association for Computational Linguistics Online conference publication zang-etal-2020-word 10.18653/v1/2020.acl-main.540 https://aclanthology.org/2020.acl-main.540/ 2020-07 6066 6080