On the Role of Lexical Features in Sequence Labeling Yoav Goldberg author Michael Elhadad author 2009-08 text Proceedings of the 2009 Conference on Empirical Methods in Natural Language Processing Philipp Koehn editor Rada Mihalcea editor Association for Computational Linguistics Singapore conference publication goldberg-elhadad-2009-role https://aclanthology.org/D09-1119/ 2009-08 1142 1151