I am regressing an outcome on two treatments using differences in differences.
To deal with the pre-trend problem, I introduced the entropy balancing method and run the regression separately on either treatment using the respective weights that are generated based on the certain treatment.
I am trying to add both treatments together and see whether they are orthogonal to each other.
But entropy balancing can only accept one binary treatment.
Is there a method to balance on two treatments?
Thank you for your help!
