Frontiers: A Simple Forward Difference-in-Differences Method
提出一种简单的前向双重差分方法，用于从准实验数据中估计因果效应，并开发了其推断理论，适用于广泛的应用场景。
I propose a simple forward difference-in-differences method to estimate causal effects from quasiexperimental data and also develop its inference theory, which is widely applicable.