Levi Graph AMR Parser using Heterogeneous Attention Han He author Jinho D Choi author 2021-08 text Proceedings of the 17th International Conference on Parsing Technologies and the IWPT 2021 Shared Task on Parsing into Enhanced Universal Dependencies (IWPT 2021) Stephan Oepen editor Kenji Sagae editor Reut Tsarfaty editor Gosse Bouma editor Djamé Seddah editor Daniel Zeman editor Association for Computational Linguistics Online conference publication he-choi-2021-levi 10.18653/v1/2021.iwpt-1.5 https://aclanthology.org/2021.iwpt-1.5/ 2021-08 50 57