Paper: From N-Grams To Collocations: An Evaluation Of Xtract

ACL ID P91-1036
Title From N-Grams To Collocations: An Evaluation Of Xtract
Venue Annual Meeting of the Association of Computational Linguistics
Session Main Conference
Year 1991

In previous papers we presented methods for retrieving collocations from large samples of texts. We described a tool, Xtract, that im- plements these methods and able to retrieve a wide range of collocations in a two stage process. These methods a.s well as other re- lated methods however have some limitations. Mainly, the produced collocations do not in- clude any kind of functional information and many of them are invalid. In this paper we introduce methods that address these issues. These methods are implemented in an added third stage to Xtract that examines the set of collocations retrieved during the previous two stages to both filter out a number of invalid col- locations and add useful syntactic information to the retained ones. By combining parsing and statistical techniques the a...