We estimate the causal impact of communication infrastructure quality on growth and structural transformation. We use variation across US counties’ Internet speeds in 2018 and build an instrument using ARPANET, a military network that preceded the modern Internet, with its location documented in historical government reports. We find that doubling Internet speeds increases the 4-year employment growth by 3.3–6.1 percentage points. Faster Internet shifts economic activity toward high-skilled services and away from non-tradeable services while increasing inequality. Industry linkages, capital-skill complementarity, and information and communication technology workers’ sorting rationalize our results. Medium and small cities and rural areas drive our results.

中文翻译：

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通信基础设施的质量、地方结构转型和不平等

我们评估了通信基础设施质量对增长和结构转型的因果影响。我们利用 2018 年美国各县互联网速度的变化，并使用 ARPANET（一种早于现代互联网的军事网络）构建了一个仪器，其位置记录在历史政府报告中。我们发现，互联网速度提高一倍会使 4 年就业增长率提高 3.3-6.1 个百分点。更快的互联网将经济活动从不可贸易的服务转向高技能服务，同时加剧了不平等。产业联系、资本技能互补以及信息和通信技术工人的排序使我们的结果合理化。中小城市和农村地区推动我们的业绩。