This doesn't answer your question, but have you considered including all 7 variables into one model and then examine the semi-partial R-squared values (assuming your dependent variable is continuous)?  You could sum those values for each of the 21 pairs to come up with a heirarchical ordering.  You could add interactions as Rick@SAS suggests to get at more complex relationships between the variables. ... View more

If I understood what your mean. you can use arrary to loop to get the result. For example. For (7, 2) You can code like: array state{7} state1-state7; do i=1 to 7; do j=i to 7; var=state{i}||state{j}; end; end; Ksharp ... View more