The Behavioral Foundations of Default Effects: Theory and Evidence from Medicare Part D
通过三个自然实验，发现联邦医疗保险D部分的默认规则对低收入参保者的注册和药物使用有巨大且持续的影响，且被动性对默认选项价值极不敏感，即使默认选项会导致重大药物消费损失。
We show in two natural experiments that default rules in Medicare Part D have large, persistent effects on enrollment and drug utilization of low-income beneficiaries. The implications of this phenomenon for welfare and optimal policy depend on the sensitivity of passivity to the value of the default option. Using random assignment to default options, we show that beneficiary passivity is extremely insensitive, even when enrolling in the default option would result in substantial drug consumption losses. A third natural experiment suggests that variation in active choice is driven by random transitory shocks rather than the inherent attentiveness of some beneficiaries.