In this paper, we consider a panel data model which allows for heterogeneous time trends at different locations. We propose a new estimation method for the panel data model before we establish an asymptotic theory for the proposed estimation method. For inferential purposes, we develop a...

In this paper, we consider a wide class of time-varying multivariate causal processes which nests many classic and new examples as special cases. We first prove the existence of a weakly dependent stationary approximation for our model which is the foundation to initiate the theoretical...

In this paper, we study the problem of allocating a limited budget to competing social treatment programs. The optimal budget allocation scheme is defined by an optimal splitting point that maximizes a social value function, weighted across different treatment programs. We propose estimators for...