Beyond Parallel Trends: An Identification-Strategy-Robust Approach to Causal Inference with Panel Data
超越平行趋势:面板因果推断的识别策略稳健方法
In this paper, we propose a new approach to causal inference with panel data. Instead of using panel data to adjust for differences in the distribution of unobserved heterogeneity between the treated and comparison groups, we instead use panel data to search for "close comparison groups" -- groups that are similar to the treated group in terms of pre-treatment outcomes. Then, we compare the outcomes of the treated group to the outcomes of these close comparison groups in…