中文摘要
我们利用一次火山“实验”研究地理迁移的成本与收益。在这次实验中，一座城镇三分之一的房屋被熔岩覆盖。居住在这些房屋中的人永久迁离的可能性要大得多。对于家庭中的受抚养人（子女），我们的估计表明，由“熔岩冲击”促成的迁移大幅提高了他们的终身劳动收入和受教育程度。尽管这些估计值很大，但也存在相当大的统计不确定性。迁移收益在代际之间的分布极不均衡：户主（父母）因这一冲击而境况略有恶化。这些结果表明，子女面临很大的迁移障碍，这意味着劳动力并未流向其能够获得最高回报的地方。考虑到受此次火山实验影响的城镇过去是、现在仍是一个相对高收入的城镇，年轻人从迁移中获得的巨大收益令人意外。我们将这些发现解读为比较优势重要性的证据：对于那些与自己碰巧出生的地方很不匹配的人而言，即使不同地方的平均收入差异很小，迁移收益也可能非常大。
Abstract
Abstract We exploit a volcanic “experiment” to study the costs and benefits of geographic mobility. In our experiment, a third of the houses in a town were covered by lava. People living in these houses were much more likely to move away permanently. For the dependents in a household (children), our estimates suggest that being induced to move by the “lava shock” dramatically raised lifetime earnings and education. While large, these estimates come with a substantial amount of statistical uncertainty. The benefits of moving were very unequally distributed across generations: the household heads (parents) were made slightly worse off by the shock. These results suggest large barriers to moving for the children, which imply that labour does not flow to locations where it earns the highest returns. The large gains from moving for the young are surprising in light of the fact that the town affected by our volcanic experiment was (and is) a relatively high income town. We interpret our findings as evidence of the importance of comparative advantage: the gains to moving may be very large for those badly matched to the location they happened to be born in, even if differences in average income are small.