Hi, I was wondering if is it possible to use the GMM (xtabond2) on a static model. I'm aware that the GMM on dynamic models require GMM-style instruments to treat the problem with the lagged dependant variable in the model. However, suppose that we don't include y(t-1) in the model, do we still can use xtabond2 command? I'm aware also that GMM models can be used to treat variables mesasured withh error (using within transformation rather than differenciation).