We test how a reduction in travel cost affects the rate and direction of scientific research. Using a fine-grained, scientist-level dataset within chemistry (1991-2012), we find that after Southwest Airlines enters a new route, scientific collaboration increases by 50%, an effect that is...

We investigate whether excessively optimistic beliefs may play a role in the persistent demand for doctoral and post-doctoral training in science. We elicit the beliefs and career preferences of doctoral students through a novel survey and randomize the provision of structured information on the...

We investigate the causes and consequences of the aging of the scientific workforce. Using novel data on the population of US chemistry faculty members over fifty years, we find that the secular increase in the age of the academic workforce has been mainly driven by the slowdown in faculty...

We investigate whether having an advisor of the same gender is correlated with the productivity of PhD science students and their propensity to stay in academic science. Our analysis is based on an original dataset covering nearly 20,000 PhD graduates and their advisors from U.S. chemistry...

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...

To examine the drivers of innovation, this paper studies the global R&D effort to fight the deadliest diseases and presents four results. We find: (1) global pharmaceutical R&D activity – measured by clinical trials – typically follows the 'law of diminishing efforts': i.e. the elasticity of...