Optimal multi‐action treatment allocation: A two‐phase field experiment to boost immigrant naturalization
研究通过两阶段实地实验，估计一个基于信件的信息宣传活动的政策规则，该规则根据移民特征分配三种不同信件，以促进瑞士苏黎世新合格移民的入籍申请。
Summary Research underscores the role of naturalization in enhancing immigrants' socio‐economic integration, yet application rates remain low. We estimate a policy rule for a letter‐based information campaign encouraging newly eligible immigrants in Zurich, Switzerland, to naturalize. The policy rule assigns one out of three treatment letters to each individual, based on their observed characteristics. We field the policy rule to one‐half of 1717 immigrants, while sending random treatment letters to the other half. Despite only moderate treatment effect heterogeneity, the policy tree yields a larger, albeit insignificant, increase in application rates compared with assigning the same letter to everyone.