We construct an endogenous growth model with random interactions where firms are subject to distortions. The TFP distribution evolves endogenously as firms seek to upgrade their technology over time either by innovating or by imitating other firms. We use the model to quantify the effects of...

In 2004, Canada changed the eligibility rules for its Scientific Research and Experimental Development (SRED) tax credit, which provides tax incentives for R&D conducted by small private firms. Difference in difference estimates show a seventeen percent increase in total R&D among eligible...

There is great interest in evaluating the impact of private equity investments on innovation and economic growth. However, there is no direct empirical evidence on the effects of such transactions on the innovation strategies of entrepreneurial firms. We fill this gap by examining a rich...

We study favoritism via hometown ties, a common source of favor exchange in China, in fellow selection of the Chinese Academies of Sciences and Engineering. Hometown ties to fellow selection committee members increase candidates' election probability by 39 percent, coming entirely from the...

We develop a theory of optimal financing for R&D-intensive firms that uses their unique features—large capital outlays, long gestation periods, high upside, and low probabilities of R&D success—that explains three prominent stylized facts about these firms: their relatively low use of debt,...

In many growth models, economic growth arises from people creating ideas, and the long-run growth rate is the product of two terms: the effective number of researchers and their research productivity. We present a wide range of evidence from various industries, products, and firms showing that...

Research Joint Ventures (RJVs) are projects that combine the research resources of different firms. A sample of RJVs supported by the U.S. Advanced Technology Program shows that the projects yield revenues that are far less than costs. Related to this point, the RJVs are subject to...

The U.S. business sector has under-invested relative to Tobin's Q since the early 2000's. We argue that declining competition is partly responsible for this phenomenon. We use a combination of natural experiments and instrumental variables to establish a causal relationship between competition...

This paper develops a theory of promotion based on evaluations by the already promoted. The already promoted show some favoritism toward candidates for promotion with similar beliefs, just as beetles are more prone to eat the eggs of other species. With such egg-eating bias, false beliefs may...

Are scientific knowledge flows embodied in individuals, or "in the air"? To answer this question, we measure the effect of labor mobility in a sample of 9,483 elite academic life scientists on the citation trajectories associated with individual articles (resp. patents) published (resp. granted)...