Detection of Heterogeneities in a Multiple Text Database Environment

As the number of text retrieval systems (search engines) grows rapidly on the World Wide Web, there is an increasing need to build search brokers (metasearch engines) on top of them. Often, the task of building an eeective and eecient metasearch engine is hindered by the heterogeneities among the underlying local search engines. In this paper, we rst analyze the impact of various heterogeneities on building a metasearch engine. We then present some techniques that can be used to detect the most prominent hetero-geneities among multiple search engines. Applications of utilizing the detected heterogeneities in building better metasearch engines will be provided.