I'm running a two way ANOVA test in SPSS v19 to look at the effect of two fixed factors (density energy and accelerated aging) on a dependent variable (flexural strenght). Results of ANOVA showed a significant effect of my two fixed factors on my dependent variable and a significant interaction between the two fixed factors.
The problem is when I perform the post hoc tests (Tukey), SPSS gives me the significance values for density energy and accelerated aging, each one for separate; I was wondering if it is possible to run a post-hoc test which includes both factors together, because until now, I cant' find how to do it in SPSS.
Any help will be great.
Thanks in advance.