Knowledge flows within and across countries should be carriers of important learning spillovers. We use data on 1.5 million patents and 4.5 million citations to analyze knowledge flows across 147 subnational regions. We estimate that only 15% of average knowledge is learned outside the average...

Knowledge flows within and across countries should be carriers of important learning spillovers. We use data on 1.5 million patents and 4.5 million citations to analyze knowledge flows across 147 subnational regions. We estimate that only 15% of average knowledge is learned outside the average...