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Overview of the TREC 2004 Robust Retrieval Track



Ellen M. Voorhees


The robust retrieval track explores methods for improving the consistency of retrieval technology by focusing on poorly performing topics. The retrieval task in the track is a traditional ad hoc retrieval task where the evaluation methodology emphasizes a system's least effective topics. The most promising approach to improving poorly performing topics is exploiting text collections other than the target collection such as the web. The 2004 edition of the track used 250 topics and required systems to rank the topics by predicted difficulty. The 250 topics within the test set allowed the stability of evaluation measures that emphasize poorly performing topics to be investigated. A new measure, a variant of the traditional MAP measure that uses a geometric mean rather than an arithmetic mean to average individual topic results, shows promise of giving appropriate emphasis to poorly performing topics while being more stable at equal topic set sizes.
Special Publication (NIST SP) - 500-261
Report Number


Voorhees, E. (2005), Overview of the TREC 2004 Robust Retrieval Track, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 20, 2024)
Created August 1, 2005, Updated November 10, 2018