I have a question about data analysis. I am analyzing data on two groups of subjects (autistics and language disordered), and originally conducted partial correlations between variables of memory and social functioning, controlling for IQ. I have been told that I also need to take the range of the variables into account, and should do some kind of analysis such as a standard error of estimate. I have not been able to find a book that talks about this issue. (the person who told me this said it is because restricted range can affect correlations). ANy ideas on what kind of analysis to conduct and how to do it in SPSS?I am mainly interested in looking at the relationship between memory and social within groups and then comparing this relationship between groups (different pattern?).