[R] normality test

Knut M. Wittkowski kmw at mail.rockefeller.edu
Tue Feb 17 14:57:08 CET 2004

Hello Samuel,

Regardless of some more fundamental problems (see below), a test to "prove" 
normality based on a sample of 9? - Fugetaboutit.


At 10:20 2004-02-06 +0100, I wrote:
>It may be tempting to interpret a non-significant result of a statistical 
>test as to verify the hypothesis, e.g., as to verify that the distribution 
>of the data is Gaussian. Unfortunately, a non-significant test is merely 
>non-conclusive (Popper KR, Wien: 1937), so one would have to test for 
>equivalence, e.g., as TOST (two one-sided tests). To do this with the a 
>test for normality (Shapiro, Lillifors, ...), however, it may be difficult 
>to come up with a justification for an equivalence limit.

At 09:32 2004-02-17 +0100, you wrote:
>I am analysing several samples whose sizes are from 9 to 110.
>I would like to test their distribution with R,
>whether they are normal or not.
>I wonder which test for normality from R should I use .
>Thank you for help.
>Laboratoire de Biomecanique
>151, bd de l'Hopital
>75013 PARIS
>Tel. +33 (0) 1 44 24 64 53
>Fax. +33 (0) 1 44 24 63 66

Knut M. Wittkowski, PhD,DSc
The Rockefeller University, GCRC
Experimental Design and Biostatistics
1230 York Ave #121B, Box 322, NY,NY 10021
+1(212)327-7175, +1(212)327-8450 (Fax)
kmw at rockefeller.edu

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