I am using modprobe syntax on SPSS to test an interaction between narcissism and rumination on a dependent variable, aggression.
I get a significant effect of rumination (b = .6450, t = 2.32, p = .0216) and significant effect of narcissism (b = .5646, t = 2.5, p = .0135). The interaction is not significant (b = -.069, t = -.824, p =. 4114).
I'm not really sure how to interpret this. Can I still look at the plot and slopes? Or are they now meaningless as they are insignificant? (Or should I look at them and try to see why it is insignificant, e.g., because narcissism lines are too close together at +1 SD of rumination?)
The modprobe output has a section called: 'conditional effect of predictor at values of the moderator'
Rumination -1sd: narcis=2.25. B= .49. T= 4.19. P= .000 Rumination Mean: narcis=3.21. .42. 4.69. .000 Rumination +1sd: narcis=4.17. B= .36. T= 2.86. P= .0048
Since all these are significant, doesn't this make the interaction significant? Basically, I'm not sure what the significance in the above table represents since the main effects' and interaction's significances are already shown elsewhere. Secondly, is it possible that the interaction is not significant because of the high p at +1 SD? All I really want to know is how to report this output, but I'm trying to grasp some understanding of it while I'm at it.