Re: ANOVA with selected comparisons?

Peter Frank wrote:
> Hello,
>
> I got a question regarding multiple comparison analysis. I have six
> samples and I am only interested in the comparisons of one group of
> three samples to the other group of three samples, which makes 9
> comparisons. Doing an ordinary ANOVA with the SNK post hoc test gives
> me more comparisons than that. Are the results still valid or do I
> have to make any corrections for being only interested in comparing
> one group of samples to the other group of samples and not any sample
> to any other sample?
Why don't you use a nested ANOVA?  Nest Samples within Groups, and test 
the Groups effect.

Bob

--
Bob O'Hara

Rolf Nevanlinna Institute
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