Another post on how to test for curvature in two-level factorial with center points, including discussion of centerpoint effect
A test for curvature in a factorial experiment is the p-value of the centerpoint effect. It is calculated by getting the statistical significance of the difference between the centerpoint value and the average of the modeled corner points. I'd like a way to see this in an ANOVA table or a lack of fit table. I'd like a way for the model fit to exclude the center points. I'd like the model to no...