Experimentally Identifying Constraints to Risk Sharing: Separating Limited Commitment, Moral Hazard and Hidden Income

发展中国家的家庭面临着很大的收入风险，而正规的信贷和保险市场往往不存在。为了应对这种风险，家庭参与非正式的风险分担，在家庭之间进行转移。这种“非正式的风险分担”一直是发展经济学研究最广泛的课题之一。虽然早期的工作集中在村庄非正式风险分担的惊人效果，最近的文献已经转移到了解具体的限制，可能是非正式保险的障碍。然而，几乎没有证据表明这种限制的相对重要性。为了有效地设计解决家庭收入风险的政策，重要的是要了解非正规保险的哪些制约因素是重要的，以及这些制约因素如何相互作用。我们的项目将设计一个实验，让我们看看约束单独以及在一起。具体而言，研究考虑了三个主要摩擦：（1）隐性收入，（2）道德风险和（3）缺乏承诺。我们的项目研究每种类型的摩擦的联合相互作用。首先，我们将建立一个包含所有三种摩擦的风险分担模型，并描述一阶方程和各种乘数。这给了我们一组修改的（逆）欧拉方程，我们可以把它带到。第二，我们将进行一个现场实验，其中个人面临的工作机会，但工作机会不同的工资是否知道一个人的风险分担的合作伙伴，是否有奖金，以及奖金的功能是否知道一个人的风险分担的合作伙伴。该理论使我们能够用带有拉格朗日乘子的（逆）欧拉方程来描述今天和明天消费之间的关系。这个实验通过外生地改变给定摩擦的重要程度，使我们有能力衡量各种约束在这个框架中的约束程度。

Households in developing countries face a lot of income risk, yet formal credit and insurance markets often do not exist. To deal with this risk, households participate in informal risk sharing, making transfers between households. This "informal risk sharing" has been one of the most widely studied topics in development economics. While early work focused on the surprising effectiveness of village informal risk sharing, more recent literature has shifted to understanding specific constraints that may be barriers to informal insurance. However, there is little evidence of the relative importance of such constraints. In order to effectively design policies to address household income risk it is important to understand which constraints to informal insurance are important, and also, how such constraints may interact with one another. Our project will design an experiment that lets us look at constraints individually as well as together. Specifically, research has considered three main frictions: (1) hidden income, (2) moral hazard and (3) lack of commitment. Our project studies the joint interaction of each type of friction. First, we will develop a risk-sharing model with all three frictions and characterize the first order equations together with the various multipliers. This gives us a set of modified (inverse) Euler equations that we can take to the. Second, we will conduct a field experiment wherein individuals face job opportunities but the job opportunities differ in terms of whether the wage is known to one's risk sharing partners, whether there is a bonus, and whether the bonus feature is known to one's risk sharing partner. The theory allows us to characterize the relationship between today and tomorrow's consumption in terms of (inverse) Euler equations with Lagrange multipliers. The experiment, by exogenously varying the degree to which a given friction can matter, gives us the power to measure the extent to which various constraints are binding in this framework.