Alternative Assumptions to Identify LATE in Fuzzy Regression Discontinuity Designs
讨论了模糊断点回归设计中识别局部平均处理效应的两种替代假设：局部独立性和局部平滑性，并比较了它们的实际含义与可检验性，对实证研究者选择假设有参考价值。
Abstract There exist two alternative assumptions to identify local average treatment effects (LATE) in fuzzy regression discontinuity (RD) designs: local independence (LI) and local smoothness (LS). Together with the usual LATE assumptions requiring existence of a first‐stage and treatment monotonicity, either of these two assumptions is sufficient to identify RD LATE. I discuss the practical (and testable) implications of these alternative assumptions, and show that weakening LI by LS might be empirically relevant. However, when LI does hold, there are some practical implications one may explore. Numerical and empirical examples are briefly presented.