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:
$$ \mathrm{MAP}=\frac{1}{n}{\displaystyle \sum_n{\mathrm{AP}}_n}\ $$


Average Precision Evaluation Metrics Mean Average Precision Ranking System Information Retrieval System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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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