Hank Stevens <[EMAIL PROTECTED]> writes: > power.t.test() requires a standard deviation as input, but for a two > sample test, I do not understand what is required. Is it the standard > deviation of the means (standard error), or of the combined sample?
The two (theoretical) distributions from which samples are drawn are assumed to have the same SD. This is the value to plug in. -- O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
