I am stuck for 2 hrs! please help!!


I have a 2 by 4 design: amount of eating (independent variable, out of 100) on stress (low vs high) and time (1, 2, 3, 4 hours). 10 subjects for each condition. We predict that amount of eating would be lower in the high stress condition. After conducting an overall test, there is a significant interaction, and significance on the time and stress factors, so we go on to do simple main effect tests. But, given that prediction of eating lower in the high stress condition, how do we go on to do the simple main effect tests?

I did factor a by b simple main effect test, and found significance in both a1 and a2 conditions. But I still don't understand how to do further tests, or even, what to do, because we have a prediction. Can someone help? Thanks.

n = 10

2-way anova:
stress
time low high
1 hr 62 50
2 hr 81 71
3 hr 72 54
4 hr 73 41

Amount of eating is