# Test of proportional changes

#### stats_newb

##### New Member
Hi all,

I'm a transfer student trying to catch up on stats in my new program (the kids at my new university are a semester ahead of me) and I've been reading this forum a lot to help me out, but I've got a problem now that I'm really stuck on.

I've got some data where we did an experiment on some bugs, males and females separately. There were two treatments for both genders, and we had controls for all (so treatment 1, and its related control, treatment 2, and its related control; 4 sets of numbers per gender) I used ANOVA to see that both the experimental treatments did have an effect on both the males and the females, and my professor said I did that right. But now the prof wants us to see if there was a difference in the degree to which the treatments affected the males and females. She hinted that we should test the proportion of change for each treatment between M and F.

I interpreted that to mean, looking at means, what's the percent difference between control 1 and treatment 1, for girls and for boys, then compare the percent difference for both genders. Then do it again for control/treatment 2. But I can't figure out how to do this! I suspect I may just be overthinking it or something but I've always been bad at math and I'm just so stumped. If anyone can make any suggestions I would really appreciate it!!

P.S. I don't know if it matters but my class uses SPSS, so I don't really know how to do stuff with long formulas and calculators :S