Psychologists Should Use Brunner-Munzel’s Instead of Mann-Whitney’s U Test as the Default Nonparametric Procedure

  title={Psychologists Should Use Brunner-Munzel’s Instead of Mann-Whitney’s U Test as the Default Nonparametric Procedure},
  author={Julian D. Karch},
  journal={Advances in Methods and Practices in Psychological Science},
  • J. Karch
  • Published 1 April 2021
  • Psychology
  • Advances in Methods and Practices in Psychological Science
To investigate whether a variable tends to be larger in one population than in another, the t test is the standard procedure. In some situations, the parametric t test is inappropriate, and a nonparametric procedure should be used instead. The default nonparametric procedure is Mann-Whitney’s U test. Despite being a nonparametric test, Mann-Whitney’s test is associated with a strong assumption, known as exchangeability. I demonstrate that if exchangeability is violated, Mann-Whitney’s test can… 
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