Interregional Contact and the Formation of a Shared Identity
利用西班牙男性应征入伍者随机分配到不同地区的自然实验，研究发现早期成年期与其他地区个体的接触能长期提升对服务地区的同情和信任，并增强来自强地方民族主义地区个体的国家认同。
We study the long-run effects of contact with individuals from other regions in early adulthood on preferences, beliefs, and national identity. We combine a natural experiment, the random assignment of male conscripts to different locations throughout Spain, with tailored survey data. Being randomly assigned to complete military service outside of one’s region of residence fosters contact with conscripts from other regions and increases sympathy and trust toward people from the region of service, as measured decades later. We also observe a long-lasting increase in identification with Spain for individuals originating from regions with strong peripheral nationalism.