Bias-Aware Confidence Intervals for Synthetic Control via Placebo-in-Time Bootstrap
通过时间安慰剂 Bootstrap 构造考虑偏差的合成控制置信区间
Synthetic control (SC) methods are among the most widely used tools for causal inference without randomization. The standard Gaussian confidence interval around the estimated effect is simple, fast, and reliably directional when the treatment signal is strong, so practitioners default to it for good reason. Most treated populations, however, are bottom-heavy in intensity, and for them the SC model's systematic bias rivals or exceeds the signal even under good pre-treatment…