Different Outcomes of the Wilcoxon—Mann—Whitney Test from Different Statistics Packages

  title={Different Outcomes of the Wilcoxon—Mann—Whitney Test from Different Statistics Packages},
  author={Reinhard Bergmann and John Ludbrook and Will Spooren},
  journal={The American Statistician},
  pages={72 - 77}
Abstract The Wilcoxon—Mann—Whitney test enjoys great popularity among scientists comparing two groups of observations, especially when measurements made on a continuous scale are non-normally distributed. Triggered by different results for the procedure from two statistics programs, we compared the outcomes from 11 PC-based statistics packages. The findings were that the delivered p values ranged from significant to nonsignificant at the 5% level, depending on whether a large-sample… 
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  • J. Ludbrook
  • Medicine
    Clinical and experimental pharmacology & physiology
  • 1995
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Individual Comparison by Ranking Methods,
  • 1943
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  • 1998