Is the spatial distribution of urban business establishments sensitive to large, temporary shocks? This paper studies the impact of the 1906 San Francisco earthquake and fire on the agglomeration of 71 industries in the city. The disaster reset location patterns as firms moved after the destruction of thousands of buildings. Using addresses gathered from city business directories between 1900 and 1930, this study asks whether industry agglomeration in San Francisco was permanently affected by the shock. While firms had dispersed after the disaster, industries largely recovered their previous clustering patterns by 1915. The distribution of firms across city blocks, however, was susceptible to the shock as many industries—particularly in manufacturing—had permanently relocated in the wake of the disaster. Industry clustering is thus resilient to shocks, even if ties to certain areas of a city are not. Together, these outcomes suggest that agglomeration economies and other dynamic forces, more than fixed local characteristics, determine firm locations at a microscale.

城市商业机构的空间分布是否对大的暂时性冲击敏感？本文研究了1906年旧金山地震和大火对城市71个产业集聚的影响。随着数千所建筑物被摧毁后公司搬迁，灾难重设了位置模式。使用从1900年到1930年之间的城市商业目录中收集的地址，该研究询问旧金山的产业集聚是否受到冲击的永久影响。尽管企业在灾难后已经分散，但各行业在1915年之前基本上恢复了以前的集群模式。然而，由于许多行业（尤其是制造业）在灾难发生后永久搬迁，因此企业在各大城市中的分布容易受到冲击。 。因此，即使与城市某些地区的联系不牢固，产业集群也能抵御冲击。总之，这些结果表明，集聚经济和其他动力，而不是固定的局部特征，在微观上决定了公司的位置。