European Firm Concentration and Aggregate Productivity
利用15个国家的微观汇总数据构建欧洲赫芬达尔指数，发现过去十年集中度上升源于经济活动向大型集中行业转移，同时资源配置效率提升贡献了欧洲生产率增长的50%，且集中度变化与生产率和配置效率正相关。
Abstract This paper derives a European Herfindahl–Hirschman concentration index from 15 micro-aggregated country datasets. In the last decade, European concentration rose due to a reallocation of economic activity toward large and concentrated industries. Over the same period, productivity gains from an increasing allocative efficiency of the European market accounted for 50% of European productivity growth while markups stayed constant. Using country-industry variation, we show that changes in concentration are positively associated with changes in productivity and allocative efficiency. This holds across most sectors and countries and supports the notion that rising concentration in Europe reflects a more efficient market environment rather than weak competition and rising market power.