How should I run an interaction test to find out the main effect of ad type?

#1
Hello everyone,

I designed an experiment. There are two types of advertisement, type 1 and type 2. 50% of my participants looked at the type 1 and told me how confusing this ad is (variable confuse1);
the other 50% looked at the type 2 and told me how confusing this second ad is(variable confuse2).

After one week, I asked them to tell me again how confusing this ad are.

So I run an repeated measures analysis in SPSS and choose "ad type" as the between subjects factor :

GLM confuse1 confuse2 BY adtype
/WSFACTOR=time 2 Polynomial
/MEASURE=confusedad
/METHOD=SSTYPE(3)
/PLOT=PROFILE(time by adtype)
/EMMEANS=TABLES(time) COMPARE ADJ(BONFERRONI)
/PRINT=DESCRIPTIVE ETASQ
/CRITERIA=ALPHA(.05)
/WSDESIGN=time
/DESIGN=adtype.


The output tells me that:

1. "time" has a significant main effect of "confuse"
2. there is no significant interaction between "time" and "ad type"

But there no information about the main effect of "ad type".


My question is:

How should I figure out whether "ad type" has a main effect of "confuse" of not?