Vocabulary mining for information retrieval: rough sets and fuzzy sets

Vocabulary mining in information retrieval refers to the utilization of the domain vocabulary towards improving the user's query. Most often queries p osed to information retrieval systems are not optimal for retrieval purpose s. Vocabulary mining allows one to generalize, specialize or perform other kinds of vocabulary-based transformations on the query in order to improve retrieval performance. This paper investigates a new framework for vocabula ry mining that derives from the combination of rough sets and fuzzy sets. T he framework allows one to use rough set-based approximations even when the documents and queries are described using weighted, i.e,, fuzzy representa tions. The paper also explores the application of generalized rough sets an d the variable precision models. The problem of coordination between multip le vocabulary views is also examined. Finally, a preliminary analysis of is sues that arise when applying the proposed vocabulary mining framework to t he Unified Medical Language System (a state-of-the-art vocabulary system) i s presented. The proposed framework supports the systematic study and appli cation of different vocabulary views in information retrieval. (C) 2000 Els evier Science Ltd. All rights reserved.