I'm trying to create a logistic regression model using a large number of variables, and I'd like to create interaction terms for them. Is there a code I can use to automatically generate interaction terms between variables, or do I have to type in each individual interaction term?
For example, If I have independent variables A, B, C, D, and E, will I have to manually write "A*B A*C A*D A*E B*C B*D..." when creating the model, or is there a simpler way of doing this?
Any help would be most appreciated,
Steve