size.test.cor2: Sample size for a test of equal Pearson or partial...

In statpsych: Statistical Methods for Psychologists

Sample size for a test of equal Pearson or partial correlation in a 2-group design

Description

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	planning value of correlation
cor2	planning value of correlation
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)

# Should return:
#  n1  n2
# 325 325

size.test.cor2(.05, .8, .4, .2, 0, 2)

# Should return:
#  n1  n2
# 245 490
 

statpsych documentation built on April 4, 2025, 3:20 a.m.