Joel Lang and Mirella Lapata. 2010. Unsupervised Induction of Semantic Roles. In Proceedings of the 2010 Annual Conference of the North American Chapter of the Association for Computational Linguistics, 939-947. Los Angeles, CA. Datasets annotated with semantic roles are an important prerequisite to developing high-performance role labeling systems. Unfortunately, the reliance on manual annotations, which are both difficult and highly expensive to produce, presents a major obstacle to the widespread application of these systems across different languages and text genres. In this paper we describe a method for inducing the semantic roles of verbal arguments directly from unannotated text. We formulate the role induction problem as one of detecting alternations and finding a canonical syntactic form for them. Both steps are implemented in a novel probabilistic model, a latent-variable variant of the logistic classifier. Our method increases the purity of the induced role clusters by a wide margin over a strong baseline. @InProceedings{lang-lapata:2010:NAACLHLT, author = {Lang, Joel and Lapata, Mirella}, title = {Unsupervised Induction of Semantic Roles}, booktitle = {Human Language Technologies: The 2010 Annual Conference of the North American Chapter of the Association for Computational Linguistics}, month = {June}, year = {2010}, address = {Los Angeles, California}, publisher = {Association for Computational Linguistics}, pages = {939--947}, url = {http://www.aclweb.org/anthology/N10-1137} } |