We consider the following problem. There is a structural equation of interest that contains an explanatory variable that theory predicts is endogenous. There are one or more instrumental variables that credibly are exogenous with regard to this structural equation, but which have limited...

We develop a simulation based approach that can determine whether the semiparametric efficiency bound of a dynamic discrete choice model with fixed effects is zero or not. We illustrate the usefulness of our approach by considering a simplified version of Keane and Wolpin's (1997) model, where...

The bounds on ATE by Chesher (2007) and Kitagawa (2009b) are compared. The difference between them is attributed to the scalar error assumption imposed by Chesher (2007).

It is examined how Bayesian inference might proceed in models with many instruments. A new prior specification based on Lancaster's (1997) parameter orthogonalization is developed. This orthogonalization is shown to guarantee that the statistical problems associated with the first stage...

It is shown that in a nonparametric nonseparable triangular system, the conditional moment restriction (CMR) does not identify the average structural function (ASF). The CMR identifies the ASF only if the model is structurally separable in observable covariates and unobservable random errors....

We study the asymptotic distribution of three-step estimators of a finite dimensional parameter vector where the second step consists of one or more nonparametric regressions on a regressor that is estimated in the first step. The first step estimator is either parametric or non-parametric....

Many social experiments are run in multiple waves, or are replications of earlier social experiments. In principle, the sampling design can be modified in later stages or replications to allow for more efficient estimation of causal effects. We consider the design of a two-stage experiment for...