Statistical Surrogacy in Sequential Policy Trials
The surrogacy condition held statistically for 2-month employment predicting 4-month employment (Wald test p = 0.575 for Syrians, p = 0.527 for Jordanians) [20]. Targeting 2-month employment in counterfactual simulations doubled the employment gains compared to a standard RCT (13.4% vs 12.4%), whereas targeting noisy 6-week employment yielded zero adaptive gains [20, 21].