TY  - CONF
ID  - www200952
UR  - http://www2009.eprints.org/52/
A1  - Broder, Andrei
A1  - Ciccolo, Peter
A1  - Gabrilovich, Evgeniy
A1  - Josifovski, Vanja
A1  - Metzler, Donald
A1  - Riedel, Lance
A1  - Yuan, Jeffrey
Y1  - 2009/04//
N2  - Sponsored search systems are tasked with matching queries to relevant advertisements. The current state-of-the-art matching algorithms expand the user?s query using a variety of external resources, such as Web search results. While these expansion-based algorithms are highly effective, they are largely inefficient and cannot be applied in real-time. In practice, such algorithms are applied o?ine to popular queries, with the results of the expensive operations cached for fast access at query time. In this paper, we describe an efficient and effective approach for matching ads against rare queries that were not processed o?ine. The approach builds an expanded query representation by leveraging o?ine processing done for related popular queries. Our experimental results show that our approach signi?cantly improves the effectiveness of advertising on rare queries with only a negligible increase in computational cost. 
TI  - Online Expansion of Rare Queries for Sponsored Search
SP  - 511
M2  - Madrid, Spain
AV  - public
EP  - 511
T2  - 18th International World Wide Web Conference
ER  -