I have two categorical variables (A and B) in a linear regression. Each is binary.
Both are statistically significant in a model without an interaction term.
When I include the interaction between them, neither the interaction term nor either of the main effects are significant.
However, if I change the reference category of A, B is significant in the model.
As I have read that the main effects in a model that includes an interaction term represent the effect of one variable when the other is 0, and my explanatory variables are binary, I am confused how this does not constitute an interaction. It seems clear that the effect of B depends on A.
Would anyone mind explaining this to me please? I am unsure how to interpret my results.