, Volume 65, Issue 1, pp 23–28 | Cite as

Sample size requirements for estimating pearson, kendall and spearman correlations

  • Douglas G. Bonett
  • Thomas A. Wright


Interval estimates of the Pearson, Kendall tau-a and Spearman correlations are reviewed and an improved standard error for the Spearman correlation is proposed. The sample size required to yield a confidence interval having the desired width is examined. A two-stage approximation to the sample size requirement is shown to give accurate results.

Key words

sample size interval estimation correlation rank correlation 


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Copyright information

© The Psychometric Society 2000

Authors and Affiliations

  • Douglas G. Bonett
    • 1
  • Thomas A. Wright
    • 2
  1. 1.Department of StatisticsIowa State UniversityAmes
  2. 2.University of NevadaReno

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