On Mon, 11 Aug 2003 12:07:35 +0200, Piotr Wi¶niewski <[EMAIL PROTECTED]> wrote:
>t-Student test >log-transformed data >------------------------ > n mean SD >X1 30 0.26 0.46 >X2 6 -0.11 0.17 > >p=0.17 Are you using the "pooled" t-test that assumes equal population variances for the two groups? If you are, this situation, where the smaller group also has the smaller SD, can give very misleading P-values. -- Ken Butler, Lecturer (Statistics) University of Toronto at Scarborough butler (at) utsc.utoronto.ca http://www.utsc.utoronto.ca/~butler . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
