TY - CONF ID - www20092 UR - http://www2009.eprints.org/2/ A1 - Guo, Fan A1 - Liu, Chao A1 - Kannan, Anitha A1 - Minka, Tom A1 - Taylor, Michael A1 - Wang, Yi-Min A1 - Faloutsos, Christos Y1 - 2009/04// N2 - Given a terabyte click log, can we build an efficient and effective click model? It is commonly believed that web search click logs are a gold mine for search business, because they re?ect users? preference over web documents presented by the search engine. Click models provide a principled approach to inferring user-perceived relevance of web documents, which can be leveraged in numerous applications in search businesses. Due to the huge volume of click data, scalability is a must. We present the click chain model (CCM), which is based on a solid, Bayesian framework. It is both scalable and incremental, perfectly meeting the computational challenges imposed by the voluminous click logs that constantly grow. We conduct an extensive experimental study on a data set containing 8.8 million query sessions obtained in July 2008 from a commercial search engine. CCM consistently outperforms two state-of-the-art competitors in a number of metrics, with over 9.7% better log-likelihood, over 6.2% better click perplexity and much more robust (up to 30%) prediction of the ?rst and the last clicked position. TI - Click Chain Model in Web Search SP - 11 M2 - Madrid, Spain AV - public EP - 11 T2 - 18th International World Wide Web Conference ER -