FDRsampsize (version 1.0)

power.twosampt: Compute power of the two-samples t-test

Description

Estimate power of the two-samples t-test;Uses classical power formula for two-sample t-test;Assumes equal variance and sample size

Usage

power.twosampt (n, alpha, delta, sigma = 1)

Arguments

n

per-group sample size (scalar)

alpha

p-value threshold (scalar)

delta

difference between population means (vector)

sigma

standard deviation (vector or scalar)

Value

Details

For many applications, the null.effect is zero difference of means.

Examples

 power.twosampt        # show the power function
 res=fdr.sampsize(fdr=0.1,
                  ave.pow=0.8,
                  pow.func=power.twosampt,
                  eff.size=rep(c(2,0),c(100,900)),
                  null.effect=0,
                  sigma=1)
 res