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Retrieval Group

We work with industry, academia and other government agencies to promote the use of more effective and efficient techniques for manipulating (largely) unstructured textual information.

The group facilitates retrieval research involving large, unstructured text files by providing test collections and organizing the TREC conference and its proceedings. We continue to create new test collections, focusing mainly on collections to support specific information retrieval sub-tasks such as cross-language retrieval and multimedia retrieval. We also develop better evaluation methodology for information access, including improved evaluation measures for comparing systems using test collections and new evaluation measures for interactive searching and browsing operations.


News and Updates


Overview of the NTCIR-17 FairWeb-1 Task

Sijie Tao, Nuo Chen, Tetsuya Sakai, Zhumin Chu, Hiromi Arai, Ian Soboroff, Nicola Ferro, Maria Maistro
This paper provides an overview of the NTCIR-17 FairWeb-1 Task. FairWeb-1 is an English web search task which seeks more than an ad-hoc web search task. Our

Too many Relevants: Whither Cranfield Test Collections?

Ellen M. Voorhees, Nick Craswell, Jimmy Lin
This paper presents the lessons regarding the construction and use of large Cranfield-style test collections learned from the TREC 2021 Deep Learning track. The

Human Preferences as dueling Bandits

Xinyi Yan, Chengxi Luo, Charles Clarke, Nick Craswell, Ellen M. Voorhees, Pablo Castells
The dramatic improvements in core information retrieval tasks engendered by neural rankers create a need for novel evaluation methods. If every ranker returns