I am doing a simple moderation analysis with one independent variable (IV), one moderator (M) and one dependent variable (DV).
Results indicate that a regression model containing both main effects (of IV and M) is non-significant. After adding the interaction term of IVxM to the previous model, the new model remains non-significant. However, the R-squared change IS significant, so the second model accounts for a significantly higher amount of the DV than model 1.
My question is:
Under these conditions, can we speak of having a moderation here?
After all, the main effects are non-significant and I believe to remember that my statistic prof told me a moderation only occurs if the model in general and both main effects are significant...
By the way, it seems as if my main effects are non-significant due to a cross-over interaction. However, I am not sure how to find out if this cross-over interaction is significant (in SPSS). Does this also have to do with the R-squared change value?