difference in difference stata psm ndm does stata compare psm with didm what is the relationship between psm and dim what is didm and psm how to calculate psm and a dimm why psm and dimm how to compare dmd and psm how to combine a dndm model and a psm can the didm and psm model be combined what model would match the psm? what is the difference between stata and didm can you use a psm score when combining stata and dimm can stata combine didm and psm what is the psm model in stata do the data in stata match a dimm what model can be used to match psm to didm what is idm and psm why is a DID model used instead of a psm what is the difference between the didm & ppsm