Demographic and ecological theories yield mixed evidence as to whether ethnic enclaves are a benefit or a hindrance to the status attainment of residents and entrepreneurs. This article provides one possible theoretical resolution by separating the positive effects that may emanate among co-ethnic neighbors from the negative effects that may result with the concentration of racial or ethnic groups. The theory is tested by analyzing occupational wage attainment and entrepreneurship among African-Americans between 1880 and 1940, a historical context in which Jim Crow laws imposed segregation exogenously. Drawing on cross-sectional and panel census data for representative samples of blacks in the United States, the results suggest consistent upward occupational mobility among residents with same-race neighbors, accompanied with downward mobility among residents who are concentrated in larger racialized enclaves. Both patterns are also observed in the distribution of entrepreneurial activity among blacks during the Jim Crow era.

中文翻译：

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Jim Crow，民族飞地和地位成就：美国黑人的职业流动，1880-1940

关于民族飞地是对居民和企业家获得地位的好处还是障碍，人口统计学和生态理论产生了混合的证据。本文通过将同族裔邻居之间可能产生的积极影响与种族或族裔群体集中可能导致的消极影响分开，提供了一种可能的理论解决方案。该理论通过分析 1880 年至 1940 年非裔美国人的职业工资获得和创业精神进行了测试，在这一历史背景下，吉姆·克劳 (Jim Crow) 法律外生地强加了种族隔离。利用美国黑人代表性样本的横截面和面板人口普查数据，结果表明，与同种族邻居的居民之间存在一致的向上职业流动，伴随着集中在更大的种族化飞地的居民之间的向下流动。在 Jim Crow 时代，在黑人创业活动的分布中也观察到了这两种模式。