中文摘要
经济成功在多大程度上取决于个人与谁进行社会互动？我们利用芬兰征兵中的一项大规模自然实验来探讨这一问题。我们的研究设计基于宿舍的按字母顺序分配, 研究表明这会在同伴构成中引致近似随机的变异。来自高收入家庭的室友对收入具有正向影响, 其中来自高收入家庭的个体所受影响最大。对这些个体而言, 室友父母收入每增加一个标准差, 其长期收入提高 5.7%。研究结果支持富人之间的劳动力市场网络是关键机制。（JEL D12, D31, G51, I32, J31, J45）
Abstract
To what extent is economic success determined by with whom individuals interact socially? We tackle this question by exploiting a large-scale natural experiment in the Finnish conscription. Our research design is based on the alphabetization of dorms, which is shown to induce as good as random variation in peer composition. Dormmates from high-income families have a positive impact on earnings, with the largest effect among individuals from high-income families. For them, a one standard deviation increase in dormmates' parental income increases long-term earnings by 5.7 percent. The results support labor market networks among the rich as the key mechanism. (JEL D12, D31, G51, I32, J31, J45)