A1725
Title: Dynamic difference-in-discontinuities
Authors: Dakyung Seong - University of Sydney (Australia) [presenting]
Shu Shen - University of California Davis (United States)
Abstract: The difference-in-discontinuities (diff-in-disc) design is a widely used empirical framework to address identification failures in the traditional regression discontinuity (RD) design due to recurring confounding treatments that utilize the same policy eligibility cutoff as the new policy of interest. The repeated treatment nature of the diff-in-disc design is formalized within a general potential outcome framework that accounts for both treatment effect heterogeneity and dynamic treatment effects, including carryover effects and path dependency in contemporaneous effects. Both standard sharp and fuzzy diff-in-disc setups are considered. New identification and estimation strategies for different scenarios are proposed, and the small sample performance of the proposed estimators is studied using Monte Carlo simulations. The proposed method is applied to a seminal study on the impact of relaxing fiscal rules, illustrating how the proposed methods complement existing approaches.
