Using Markov Chains to Exploit Word Relationships in Information Retrieval

Document expansion and query expansion aim to add related terms into document and query representations in order to make them more complete. However, most previous studies are limited in two respects: They use either query expansion or document expansion, but not both; expansion has been limited to directly related words. In this paper, we propose a more general approach: both document and query representations are expanded, and the expansion process also exploits indirect term relationships. The whole process is implemented through Markov chains. Our experiments show that each of these extensions brings additional improvements.