We explore whether the generally construed positive effects of intergenerational upward mobility and racial desegregation, under increasing local knowledge stocks, are positively associated with regional entrepreneurial activity. We find the opposite association in a sample of 2,717 US counties. Our results imply that, when county-level knowledge stocks are high, the American Dream (of greater intergenerational upward mobility) and the American Melting Pot (of lower racial segregation) appear, at a minimum, to be not associated with greater entrepreneurial activity. The results are robust to a variety of alternate specifications. For example, when Metropolitan Statistical Area data are used in lieu of county-level data, the results are broadly consistent with those in the main results.

中文翻译：

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美国梦、大熔炉和地区知识储备是创业活动的驱动力

我们探讨了在地方知识储备增加的情况下，代际向上流动和种族隔离的普遍解释的积极影响是否与区域创业活动呈正相关。我们在 2,717 个美国县的样本中发现了相反的关联。我们的结果表明，当县级知识存量高时，美国梦（更大的代际向上流动性）和美国大熔炉（更低的种族隔离）似乎与更大的创业活动无关。结果对各种替代规范都很稳健。例如，当使用都市统计区数据代替县级数据时，结果与主要结果大体一致。