Synonyms
ERR
Definition
Expected reciprocal rank (ERR) is an information retrieval evaluation measure suitable for navigational queries, where the user requires only a small number of relevant documents. It generalizes reciprocal rank, which is based on binary relevance and considers only the first relevant document retrieved. Let Pr(r) denote the probability that the user is satisfied with a document at rank r. ERR assumes that the user stops scanning the ranked list as soon as she is satisfied with a document and that this satisfaction probability depends directly and solely on the relevance level of each document. For example, we can assume that Pr(r) = 0 if the document at r is nonrelevant; if we have partially relevant, relevant, and highly relevant documents (i.e., three relevance levels), we may let Pr(r) be (21 − 1)∕23 = 1∕8, (22 − 1)∕23 = 3∕8, and (23 − 1)∕23 = 7∕8, respectively. Under the linear traversalassumption (i.e., the user scans the list top down), the probability...
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsAuthor information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 Springer Science+Business Media, LLC, part of Springer Nature
About this entry
Cite this entry
Sakai, T. (2018). Expected Reciprocal Rank. In: Liu, L., Özsu, M.T. (eds) Encyclopedia of Database Systems. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-8265-9_80617
Download citation
DOI: https://doi.org/10.1007/978-1-4614-8265-9_80617
Published:
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4614-8266-6
Online ISBN: 978-1-4614-8265-9
eBook Packages: Computer ScienceReference Module Computer Science and Engineering