PSY 555 Homework 15


Chapter 9: #9,12,17,23,24,25


1.   Please describe the effects of range restrictions and heterogeneous subsamples.


2.   A study found a correlation of r=.53 between two variables.  Another researcher found a correlation of r=.42.  I am interested in comparing these two correlations.


a.  Please state the null and alternative hypotheses.


b.  Given that a z of 2.5 was found, please interpret the results using a significance level of .05.