Negative Training Data Can be Harmful to Text Classification Xiao-Li Li author Bing Liu author See-Kiong Ng author 2010-10 text Proceedings of the 2010 Conference on Empirical Methods in Natural Language Processing Hang Li editor Lluís Màrquez editor Association for Computational Linguistics Cambridge, MA conference publication li-etal-2010-negative https://aclanthology.org/D10-1022/ 2010-10 218 228