Hi! I have a design with two categorical iv and one continuous iv with a continuous dv. I wanted to see if there was a main effect or interaction from the categorical ivs, so I used the syntax:
glm DV by IV1 IV2.
There were no significant interactions or main effects. I wanted to then add in the third and continuous iv, so I ran:
glm DV by IV1 IV2 with IV3/
design=IV1 IV2 IV3 IV1*IV3 IV2*IV3 IV1*IV2*IV3.
I'm confused if I did something wrong because the F and p values for IV1 and IV2 are different from the earlier output. Why is this and which one would I report?
Thanks so much!