Hello all,

I am trying to test for the equivalence of marginal effects of the same variable at two different indicator variable set points after a regression with an interaction term. Here is the jist of my commands:

reg Y c.X1 i.dummy c.X1#i.dummy
margins dy/dx(X1) at(dummy=0 dummy=1) post

Then I would like to test for whether the marginal effect of X1 at dummy=0 is different than the marginal effect of X1 at dummy=1. I am having trouble with referring to the same variable within the same test command. i.e.: test X1=X1. Thank you in advance for what I am sure is a very simple solution.

Karen.