The issue of whether firm productivity is affected by agglomeration externalities is a longstanding area of research. However, the appropriate geographical level to better detect the effects of agglomeration economies and at which level these externalities work is still unclear. Using detailed firm-level longitudinal data on 4927 manufacturing firms in the United Kingdom over the period 2008–2016, we investigate the relation between the microgeography of external agglomeration economies and firm productivity. We compare different geographical levels: city-wide and narrowly defined neighborhoods around a firm. Results from a multilevel (mixed-effect) model show that urbanization externalities play a role at a higher level of geographical aggregation, such as the city, whereas localization externalities operate at a finer level, within the city and in a closer neighborhood to the firm. Failing to control for more granular levels of geography results in confounding the two types of externalities. We also provide novel evidence that these externalities vary across firm (such as age, size, and productivity) and location (such as population density) characteristics.

中文翻译：

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太近不舒服？英国集聚经济的微观地理

企业生产力是否受集聚外部性影响的问题是一个长期存在的研究领域。然而，更好地检测集聚经济影响的适当地理层面以及这些外部性在哪个层面起作用仍不清楚。我们使用 2008 年至 2016 年期间英国 4927 家制造企业的详细企业级纵向数据，研究了外部集聚经济的微观地理与企业生产率之间的关系。我们比较了不同的地理层面：公司周围的全市和狭义的社区。多级（混合效应）模型的结果表明，城市化外部性在更高的地理聚集水平上发挥作用，例如城市，而本地化外部性在更精细的水平上发挥作用，在城市内和离公司更近的街区。无法控制更细粒度的地理级别会导致混淆两种类型的外部性。我们还提供了新的证据，证明这些外部性因公司（例如年龄、规模和生产力）和位置（例如人口密度）特征而异。