This paper analyzes conditions under which various k-class estimators are asymptotically normal in a simultaneous equations framework with many weak instruments. In particular, our paper extends the many instruments asymptotic normality results obtained by Morimune (1983), Bekker (1994), Angrist...

This paper develops Wald-type tests for general (possibly nonlinear) restrictions in the context of a weakly-identified heteroskedastic IV regression. In particular, it is first shown that, in a framework with many weak instruments, consistency and asymptotic normality can be obtained when...

This paper considers models with time-varying individual effects (also known as factor models). The paper extends Ahn, Lee and Schmidt, Journal of Econometrics, 2001 and Bai, Econometrica, 2003 to allow a parametric function of time for the time factor. It provides a fixed-effects treatment of...

We analyze an entry game with multiple periods, in each period of which privately informed agents who have not joined yet decide whether to subscribe to a network, and subscribers derive benefits in future periods depending on the network size. We study the case that the agents are sufficiently...

We model how excess demand or excess supply can be generated in the presence of a social network of interactions, where agents are subject to external information and individual incentives. In this context we study price fluctuations in financial markets under equilibrium. In particular, we...

Instrumental Variables (IV) methods identify internally valid causal effects for individuals whose treatment status is manipulable by the instrument at hand. Inference for other populations inevitably requires some sort of homogeneity assumption. I develop a simple theoretical framework that...

This paper proposes shrinkage methods in instrumental variable estimations to solve the ``many instruments'' problem. Even though using a large number of instruments reduces the asymptotic variances of the estimators, it has been observed both in theoretical works and in practice that in finite...

Researchers, policymakers, and parents are giving education reforms involving expanded school choice increased attention. Many view the heightened competition that would presumably result from such reforms as a panacea for the ills currently plaguing the public education system in the US....

We provide an argument for the limitation of Edgeworth expansions to many commonly used statistics in the weak instrument framework. However, we show that Edgeworth expansions hold for approximately similar tests regardless of the identification conditions. Finally, we consider simulation...