Reducing infrequent-token perplexity via variational corpora Yusheng Xie author Pranjal Daga author Yu Cheng author Kunpeng Zhang author Ankit Agrawal author Alok Choudhary author 2015-07 text Proceedings of the 53rd Annual Meeting of the Association for Computational Linguistics and the 7th International Joint Conference on Natural Language Processing (Volume 2: Short Papers) Chengqing Zong editor Michael Strube editor Association for Computational Linguistics Beijing, China conference publication xie-etal-2015-reducing 10.3115/v1/P15-2101 https://aclanthology.org/P15-2101/ 2015-07 609 615