[R] t_test and power

[Malerba Giovanni]

Hi all,
I would like to estimate the sample size I need to perform some
studies. I 'll will compare 2 groups (A and B) for several quantitative
traits. I saw that R has power.t.test() function to compute the
estimation. My concern is that I know that N_group_A = 3 * N_group_B in
terms of size (and not N_group_A = N_group_B). Is there a way, using R, to
estimate the sample size I need, given that I know the ratio between size of group
A and group B?
Thank you,
Giovanni Malerba



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