We use panel data from the Panel Study of Income Dynamics (PSID) to document the changing volume and rate of intercounty migration among the poor. We evaluate whether the exchange of migrants between metro and nonmetro counties has exacerbated spatial disparities in poverty and whether some nonmetro counties have become “collecting grounds” for America's poor. The PSID highlights exceptionally high rates of intercounty migration among the nonmetro population, but especially among the poor. The results show that rural poor migrants circulate among nonmetro counties, often from one poor county to an even poorer one. This circulation of poor rural migrants has exacerbated the concentration of poverty in the most economically disadvantaged nonmetro counties. Concentrated poverty also is exacerbated by the migration of the “best and brightest” from nonmetro-to-metro counties, which also is associated with upward residential attainment (to counties with lower poverty rates). Significantly, metro-to-nonmetro migration is both selective of the poor and strongly associated with downward residential mobility to poorer nonmetro counties. Our findings are consistent with the hypothesis that poor nonmetro counties have become collecting grounds for America's poor.

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县际迁移和贫困的空间集中：比较地铁和非地铁模式*

我们使用来自收入动态面板研究的面板数据(PSID) 记录贫困人口中县际迁移的数量和比率的变化。我们评估了地铁和非地铁县之间的移民交换是否加剧了贫困的空间差异，以及一些非地铁县是否已成为美国穷人的“聚集地”。PSID 强调了非都市人口中异常高的县际迁移率，尤其是在穷人中。结果表明，农村贫困流动人口在非都市县之间流动，通常从一个贫困县流向更贫困的县。这种贫困农民工的流动加剧了贫困在经济最落后的非都市地区的集中。“最优秀和最聪明的人”从非地铁县迁移到地铁县也加剧了集中贫困，这也与住宅获得率上升（贫困率较低的县）有关。重要的是，从地铁到非地铁的迁移既对穷人有选择性，又与向较贫困的非地铁县的住宅向下流动密切相关。我们的研究结果与贫困的非地铁县已成为美国穷人的聚集地的假设是一致的。