Confidence Interval, Difference between Independent Correlations (3 of 4)
The experiment shows that there is still uncertainty about the
difference in correlations. It could be that the correlation for
females is as much as 0.49 higher. However, it could also be 0.15 lower.
Summary of Computations
Compute the sample r's.
Use an r to z' table to
convert the values of r to z'.
Compute z'1 - z'2.
Use a to z
table to find the value of
z for the level of confidence desired.
Compute:
Lower
limit = z'1 - z'2 - (z)()
Upper
limit = z'1 - z'2 + (z)()
Use
an r to z' table to convert the
lower and upper limits to r's.