I believe this question should be relatively simple. I have a 2x2 repeat measures anova for a performance task. My two factors are presence and absence of an observer and presence and absence of music playing in the background, therefore my 4 conditions are (1)no observer-no music, (2)observer-no music, (3)no observer-music, and (4)observer-music. For my measure, (after a significant anova test) I would like to use a post-hoc contrast to find out if conditions 1 and 2 are different from 3 and 4, and if conditions 1 and 3 are different from conditions 2 and 4. What test should I use and what controls do I need?
Thanks for any help!
Thanks for any help!