This paper studies the impact of U.S. immigration barriers on global knowledge production. We present four key findings. First, among Nobel Prize winners and Fields Medalists, migrants to the U.S. play a central role in the global knowledge network – representing 20-33% of the frontier...

We investigate the role played by different fields of academic knowledge and various types of higher education institutions in the emergence of innovative start-ups in a region. We show that education and research in the applied and natural sciences have the strongest effect on the emergence of...