. We show that our models are unit invariant. We also describe another appealing characteristic of our model, that is …, efficiency invariant, as a consequence of inverse structure. An illustrative example is provided to explain the proposed model …

covariance estimates as well as of an asymptotically uniformly most powerful invariant (AUMPI) test based on the likelihood ratio …

derive necessary and sufficient conditions for parallel trends that clarify whether and how selection can depend on time-invariant …