I have been told to take a closer look at: http://www.quantpsy.org/corrtest/corrtest.htm but how exactly does this work?
E.g. Given two groups of data
B, each with one explanatory variable and one response variable, each with e.g.
n=20 data points, I can calculate Spearman's Correlation Coefficient
SCC = 0.9 in group
A and in group
B I get
From the above, it is obvious that in group
A the data is well correlated with a slope
>0 and in group
B also well correlated, but with a slope
<0, so definitely a difference - Right?
Now to the real question: The
SCC quantifies in a non-parametric way how well correlated the explanatory and response variables are, but I am not sure I understand how it works with testing the difference between two correlations? I am thinking that testing
SCC=0.8 should not yield anything, since basically one correlation is rather weak and the other is sort of ok? But the link yields