document: Query topic detection for reformulation In this paper , we show that most multiple term queries include more than one topic and users usually reformulate their queries by topics instead of terms . In order to provide empirical evidence on user 's reformulation behavior and to help search engines better handle the query reformulation problem , we focus on detecting internal topics in the original query and analyzing users . reformulation to those topics . Particularly , we utilize the Interaction Information ( II ) to measure the degree of one sub-query being a topic based on the local search results . The experimental results on query log show that : most users reformulate query at the topical level ; and our proposed II-based algorithm is a good method to detect topics from original queries .
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