Why U.S. Tech Inventors Are So Highly Clustered

The clustering force: It’s the big reason behind the comeback of cities, and perhaps the most powerful driver of the knowledge economy. Alfred Marshall identified the economic power of clustering, or agglomeration, way back in the 1890s. Jane Jacobs later documented its role in catalyzing innovation and propelling the wealth of cities. The Nobel Prize-winning economist Robert Lucas described it as the underlying engine of today’s knowledge-based creative economy.

Previous research has documented the importance of clustering to high-tech startups and industries. Now, in a new working paper from the National Bureau of Economic Research, economist Enrico Moretti of the University of California, Berkeley, examines the role of clustering on more than 4 million patents in high-tech fields that were filed and granted between 1971 and 2007, a period that spans the rapid evolution of the innovative knowledge economy.