rdif.nul: Null hypothesis for difference in two correlations
Description
Tests the hypothesis that two correlations are significantly different
Usage
rdif.nul(r1, r2, n1, n2)
Arguments
r1
Correlation 1
r2
Correlation 2
n1
Sample size for r1
n2
Sample size for r2
Value
Returns a table with 2 elements
zDIF
z value for the H0
p
p value
Details
First converts r to z' for each correlation. Then constructs a z test for the difference
z <- (z1 - z2)/sqrt(1/(n1-3)+1/(n2-3))
References
Cohen, J., Cohen, P., West, S. G., & Aiken, L. S. (2003).
Applied multiple regression/correlation analysis for the behavioral sciences (3rd ed.).
Mahwah, NJ: Lawrence Erlbaum.