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An Estimate of Effect Size Based on the Mann-Whitney Statistic



James H. Yen


Meta analysis, the statistical synthesis of results from several different studies, often involves combining estimates of effect sizefrom several experiments. The standardized mean difference is one of the most commonly used estimates of effect size; however, when the data are not normally distributed, nonparametric effect size estimates may be preferable. This paper presents a nonparametric estimate of effect size based on the Mann Whitney test that combines excellent efficiency with robustness. In addition, estimates of variance and confidence interval procedures for this estimator are provided


meta-analysis, nonparametrics, robust statistics, wolcoxon test


Yen, J. (2008), An Estimate of Effect Size Based on the Mann-Whitney Statistic, Biometrics (Accessed July 16, 2024)


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Created October 16, 2008