Character-level Analysis of Semi-Structured Documents for Set Expansion Richard C Wang author William W Cohen 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 wang-cohen-2009-character https://aclanthology.org/D09-1156/ 2009-08 1503 1512