Encyclopedia of Database Systems

Living Edition
| Editors: Ling Liu, M. Tamer Özsu


Living reference work entry
DOI: https://doi.org/10.1007/978-1-4899-7993-3_492-2



The Mean Average Precision (MAP) is the arithmetic mean of the average precision values for an information retrieval system over a set of n query topics. It can be expressed as follows:
$$ \mathrm{MAP}=\frac{1}{n}{\displaystyle \sum_n{\mathrm{AP}}_n}\ $$


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Recommended Reading

  1. 1.
    National Institute of Standards and Technology. TREC-2004 common evaluation measures. Available online at: http://trec.nist.gov/pubs/trec14/appendices/CE.MEASURES05.pdf. Retrieved on 27 Aug 2007.
  2. 2.
    Sakai T. Alternatives to BPref. In: Proceedings of 33rd Annual International ACM SIGIR Conference on Research and Development in Information Retrieval; 2007. p. 71–8.Google Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Telcordia TechnologiesPiscatawayUSA
  2. 2.Twitter, IncSan FranciscoUSA
  3. 3.Georgetown UniversityWashingtonUSA