[R] Comparison of correlation coefficients

[Anupam Tyagi]

Peter Dalgaard <p.dalgaard <at> biostat.ku.dk> writes:

> No, he wants to compare two correlation coefficients, not test that
> one is zero. That's usually a misguided question, but if need be, the
> Fisher z transform atanh(r) can be used to convert r to an
> approximately normal variate with a known variance 1/(N-3) and
> comparing r1 and r2 from two independent samples is straightforward.
> The correlated case (like cor(x,y) vs cor(x,z)) is more complicated.

It seem the more complicated case is often of more substantive interest in many
settings: is children's income more strongly correlated with parent's education
than parent's income?