Approximating the Shapiro-Wilk W-test for non-normality
- Patrick Royston
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A new approximation for the coefficients required to calculate the Shapiro-WilkW-test is derived. It is easy to calculate and applies for any sample size greater than 3. A normalizing transformation for theW statistic is given, enabling itsP-value to be computed simply. The distribution of the new approximation toW agrees well with published critical points which use exact coefficients.
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- Approximating the Shapiro-Wilk W-test for non-normality
Statistics and Computing
Volume 2, Issue 3 , pp 117-119
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- Kluwer Academic Publishers
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- Patrick Royston (1)
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- 1. Department of Medical Physics, Royal Postgraduate Medical School, Ducane Rood, W12 0NN, London