Efficient Methods for Inferring Large Sparse Topic Hierarchies Doug Downey author Chandra Bhagavatula author Yi Yang 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 1: Long Papers) Chengqing Zong editor Michael Strube editor Association for Computational Linguistics Beijing, China conference publication downey-etal-2015-efficient 10.3115/v1/P15-1075 https://aclanthology.org/P15-1075/ 2015-07 774 784