Explicit Search Result Diversification through Sub-queries [chapter]

Rodrygo L. T. Santos, Jie Peng, Craig Macdonald, Iadh Ounis
2010 Lecture Notes in Computer Science  
Queries submitted to a retrieval system are often ambiguous. In such a situation, a sensible strategy is to diversify the ranking of results to be retrieved, in the hope that users will find at least one of these results to be relevant to their information need. In this paper, we introduce xQuAD, a novel framework for search result diversification that builds such a diversified ranking by explicitly accounting for the relationship between documents retrieved for the original query and the
more » ... le aspects underlying this query, in the form of sub-queries. We evaluate the effectiveness of xQuAD using a standard TREC collection. The results show that our framework markedly outperforms state-ofthe-art diversification approaches under a simulated best-case scenario. Moreover, we show that its effectiveness can be further improved by estimating the relative importance of each identified sub-query. Finally, we show that our framework can still outperform the simulated bestcase scenario of the state-of-the-art diversification approaches using subqueries automatically derived from the baseline document ranking itself. Background and Related Work The problem of diversifying search results can be stated as: Given a query q, retrieve a ranking of documents R(q) with maximum relevance with respect to q and minimum redundancy with respect to its coverage of the possible aspects underlying q.
doi:10.1007/978-3-642-12275-0_11 fatcat:pcjesatrffg2zjjp5s4niqn3ne