Computes the sample size required to test equality of two Pearson or partial
correlation with desired power in a 2-group design. Set s = 0 for a Pearson
correlation. Set R = 1 for equal sample sizes.
Usage
size.test.cor2(alpha, pow, cor1, cor2, s, R)
Arguments
- alpha
alpha level for hypothesis test
- pow
desired power
- cor1
correlation planning value for group 1
- cor2
correlation planning value for group 2
- s
number of control variables
- R
n2/n1 ratio
Value
Returns the required sample size for each group
Examples
size.test.cor2(.05, .8, .4, .2, 0, 1)
#> n1 n2
#> 325 325
# Should return:
# n1 n2
# 325 325
size.test.cor2(.05, .8, .4, .2, 0, 2)
#> n1 n2
#> 245 490
# Should return:
# n1 n2
# 245 490