The effects of individual organisations on the location of invention in the United States is underexplored. A handful of companies generate most of the inventions in most American cities and their actions do not average out in the aggregate. Temporal stability in city system properties corroborates agglomeration theories built on models of monopolistic competition that treat all firms as small and uninfluential. However, substantial churn in patenting occurs in individual cities. Churn is associated with the strategic choices made by particular firms as they expand and contract their inventive assets. The effects of idiosyncratic decisions on levels and growth of patenting are revealed. A novel inverse-size volatility hypothesis is tested that is consistent with a claim that beyond the largest most inventive cities individual organisations are highly influential and identifiable. The findings are compatible with recognition that variety in market structures is essential to understanding the location and growth of invention in the American urban system.

中文翻译：

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美国发明地点的组织和变化动态


美国各个组织对发明地点的影响尚未得到充分探讨。美国大多数城市的大部分发明都是由少数公司创造的，但它们的行动总体上并不平均。城市系统属性的时间稳定性证实了建立在垄断竞争模型基础上的集聚理论，该理论将所有企业视为小型且无影响力的企业。然而，个别城市的专利申请量出现大幅波动。流失与特定公司在扩大和收缩其发明资产时做出的战略选择有关。特殊决策对专利申请水平和增长的影响被揭示。测试了一种新颖的反规模波动性假说，该假说与以下说法一致：除了最大的最具创造力的城市之外，个别组织具有高度影响力和可识别性。这些发现与这样的认识相一致：市场结构的多样性对于理解发明在美国城市系统中的位置和增长至关重要。