Because of scale effects, idea-based growth models have the counterfactual implication that larger countries should be much richer than smaller ones. New trade models share this same problematic feature: although small countries gain more from trade than large ones, this is not strong enough to...

Although economists have long been interested in the implications of Marshallian externalities (i.e., industry-level external economies of scale) for trading economies, the large number of equilibria that they typically imply has kept such externalities out of the recent quantitative trade...

Conventional analysis in the trade-industrial-organization literature suggests that, when a country has some market power over an imported good, some small level of protection must be welfare improving. This is essentially a terms-of-trade argument that is reinforced if the imported goods are...

Increasing returns are as fundamental a cause of international trade as comparative advantage, but their role has until recently been neglected because of the problem of modelling market structure. Recently substantial theoretical progress has been made using three different approaches. These...

There are two principal theories of why countries or regions trade: comparative advantage and increasing returns to scale. Yet there is virtually no empirical work that assesses the relative importance of these two theories in accounting for production structure and trade. We use a framework...

This paper derives a portfolio diversification rationale for a trade policy regime that insures returns to nondiversifiable human capital investment. In the absence of complete insurance markets for human capital, the decentralized equilibrium is characterized by excessive specialization. The...

This paper evaluates the extent of adverse selection in life insurance and annuities in international markets, for both group and individual products. We also compare results with prior analyses of adverse selection in international annuity markets, focusing on the US, the UK, and Japan. Our...

A positive correlation between insurance coverage and ex post risk can be an indicator for private information in insurance markets. However, this test fails if agents have heterogeneous risk attitudes. We propose a new test that conditions on unobserved types of individuals who differ in their...

We present a graphical framework for analyzing both theoretical and empirical work on selection in insurance markets. We begin by using this framework to review the "textbook" adverse selection environment and its implications for insurance allocation, social welfare, and public policy. We then...

Across a wide set of non-group insurance markets, applicants are rejected based on observable, often high-risk, characteristics. This paper argues private information, held by the potential applicant pool, explains rejections. I formulate this argument by developing and testing a model in which...