We thank Lakshmi Aiyar, Shawn Cole, Stijn Claessens, Oded Galor, Adair Morse, Mark Rosenzweig, Jeremy Stein, as well as participants in seminars at the IMF, the NBER Political Economy, Corporate Finance, and Growth Workshops, M.I.T., Northwestern University, the University of Chicago, the WFA...

We study the evolution of profits, investment and market shares in US industries over the past 40 years. During the 1990's, and at low levels of initial concentration, we find evidence of efficient concentration driven by tougher price competition, intangible investment, and increasing...

For the first four decades of its existence the U.S. nuclear power industry was run by regulated utilities, with most companies owning only one or two reactors. Beginning in the late 1990s electricity markets in many states were deregulated and almost half of the nation's 103 reactors were sold...

We examine whether and to what extent consolidation in the U.S. health insurance industry is leading to higher employer-sponsored insurance premiums. We make use of a proprietary, panel dataset of employer-sponsored healthplans enrolling over 10 million Americans annually between 1998 and 2006...

We study the importance of discretion in antitrust enforcement by analyzing the response of asset prices to the sudden accession of Theodore Roosevelt to the presidency. During McKinley's term in office the largest wave of merger activity in American history occurred, and his administration did...

Financial network structure is an important determinant of systemic risk. This paper examines how the U.S. interbank network evolved over a long and important period that included two key events: the founding of the Federal Reserve and the Great Depression. Banks established connections to...

This paper compares two possible formats for free trade in the Americas: a system of spokes surrounding a U.S. hub, and a free trade area. The paper identifies the sources of welfare change, and it argues that a country's attitude towards a system depends on whether the arrangement is a...

Previous research in the US has found negative health effects of contamination when it triggers regulatory violations. An important question is whether levels of contamination that do not trigger a health-based violation impact health. We study the impact of drinking water contamination in...

U.S. county data for the last 20 or 30 years show that manufacturing employment has been deconcentrating. In contrast, the service sector exhibits concentration in counties with intermediate levels of employment. This paper presents a theory where local sectoral growth is driven by technological...