Statistical Language Models for Information Retrieval ChengXiang Zhai author 2007-04 text Proceedings of the Human Language Technology Conference of the NAACL, Companion Volume: Tutorial Abstracts Marti Hearst editor Gina-Anne Levow editor James Allan editor Association for Computational Linguistics Rochester, New York conference publication zhai-2007-statistical https://aclanthology.org/N07-5002/ 2007-04 3 4