A Hidden Markov Model Information Retrieval System

We present a new method for information retrievalusing hidden Markov models (HMMs). We develop a general framework for incorporating multiple word generation mechanisms within the same model. We then demonstrate that an extremely simple realization of this model substantially outperforms standard tf :idf ranking on both the TREC-6 and TREC-7 ad hoc retrieval tasks. We go on to present a novel method for performing blind feedback in the HMM framework, a more complex HMM that models bigram production, and several other algorithmic re nements. Together, these methods form a state-of-the-art retrieval system that ranked among the best on the TREC-7 ad hoc retrieval task.

• Type: Conference
• Year: 1999
• Where: SIGIR
• Authors: David R. H. Miller, Tim Leek, Richard M. Schwartz
• Keywords: Ad Hoc Retrieval, Hoc Retrieval Task, Information Management, SIGIR 1999, TREC-7 Ad Hoc