What happens to firms’ innovation activities when new firms enter or leave their urban neighbourhood? We empirically explore the role of knowledge spillovers through firm dynamics using firm-level panel data from Berlin. The results indicate that an increase in firm activities in the neighbourhood through entries and influx positively relates to incumbents’ innovation activities. This finding is restricted to diversity externalities which work on a very small microgeographic scale, vanishing already after a quarter of a kilometre. For specialisation externalities through firm dynamics, we cannot find a link to innovation in incumbents.

中文翻译：

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城市社区和创新中的企业动态：微观地理分析


当新企业进入或离开城市社区时，企业的创新活动会发生什么变化？我们使用柏林的企业层面面板数据，通过企业动态实证探索知识溢出的作用。结果表明，通过进入和流入而增加的邻近企业活动与现有企业的创新活动呈正相关。这一发现仅限于多样性外部性，这种外部性在非常小的微观地理范围内发挥作用，在四分之一公里后就消失了。对于通过企业动态产生的专业化外部性，我们无法找到与现有企业创新的联系。