TY - CONF TI - Diversifying Search Results AU - Agrawal, Rakesh AU - Gollapudi, Sreenivas AU - Halverson, Alan AU - Ieong, Samuel T3 - WSDM '09 AB - We study the problem of answering ambiguous web queries in a setting where there exists a taxonomy of information, and that both queries and documents may belong to more than one category according to this taxonomy. We present a systematic approach to diversifying results that aims to minimize the risk of dissatisfaction of the average user. We propose an algorithm that well approximates this objective in general, and is provably optimal for a natural special case. Furthermore, we generalize several classical IR metrics, including NDCG, MRR, and MAP, to explicitly account for the value of diversification. We demonstrate empirically that our algorithm scores higher in these generalized metrics compared to results produced by commercial search engines. C1 - New York, NY, USA C3 - Proceedings of the Second ACM International Conference on Web Search and Data Mining DA - 2009/// PY - 2009 DO - 10.1145/1498759.1498766 DP - ACM Digital Library SP - 5 EP - 14 LA - en PB - ACM SN - 978-1-60558-390-7 UR - http://doi.acm.org/10.1145/1498759.1498766 Y2 - 2019/01/27/21:41:12 ER - TY - CONF TI - An Axiomatic Approach for Result Diversification AU - Gollapudi, Sreenivas AU - Sharma, Aneesh T3 - WWW '09 AB - Understanding user intent is key to designing an effective ranking system in a search engine. In the absence of any explicit knowledge of user intent, search engines want to diversify results to improve user satisfaction. In such a setting, the probability ranking principle-based approach of presenting the most relevant results on top can be sub-optimal, and hence the search engine would like to trade-off relevance for diversity in the results. In analogy to prior work on ranking and clustering systems, we use the axiomatic approach to characterize and design diversification systems. We develop a set of natural axioms that a diversification system is expected to satisfy, and show that no diversification function can satisfy all the axioms simultaneously. We illustrate the use of the axiomatic framework by providing three example diversification objectives that satisfy different subsets of the axioms. We also uncover a rich link to the facility dispersion problem that results in algorithms for a number of diversification objectives. Finally, we propose an evaluation methodology to characterize the objectives and the underlying axioms. We conduct a large scale evaluation of our objectives based on two data sets: a data set derived from the Wikipedia disambiguation pages and a product database. C1 - New York, NY, USA C3 - Proceedings of the 18th International Conference on World Wide Web DA - 2009/// PY - 2009 DO - 10.1145/1526709.1526761 DP - ACM Digital Library SP - 381 EP - 390 LA - en PB - ACM SN - 978-1-60558-487-4 UR - http://doi.acm.org/10.1145/1526709.1526761 Y2 - 2019/01/27/22:06:28 ER -