We ask what level of migration would maximize world welfare. We find that skill-neutral policies are never optimal. An egalitarian welfare function induces a policy that entails moving mainly unskilled immigrants into the rich countries, whereas a welfare function skewed highly towards the rich...

We consider the design and implementation of international trade agreements when: (i) negotiations are undertaken and commitments made in the presence of uncertainty about future political pressures; (ii) governments possess private information about political pressures at the time that the...

Motivated by the structure of WTO negotiations, we analyze a bargaining environment in which negotiations proceed bilaterally and sequentially under the most-favored-nation (MFN) principle. We identify backward-stealing and forward-manipulation problems that arise when governments bargain under...

We describe recent work on the theory of trade agreements that speaks to the purpose and design of GATT. Our discussion proceeds in three steps. First, we examine the purpose of a trade agreement. In both the traditional economic and the political-economy approaches to the study of trade...

Empirical studies have repeatedly documented the countercyclical nature of trade barriers. In this paper, we propose a simple theoretical framework that is consistent with this and other empirical regularities in the relationship between protection and the business cycle. We examine the ability...

We present a theory of collusive pricing in markets subject to business cycle fluctuations. In the business cycle model that we adopt, market demand alternates stochastically between fast-growth (boom) and slow-growth (recession) phases. We provide a complete characterization of the...

We reexamine several bodies of data on the growth of output, labor, and capital, within the context of a model that admits the possibility of an externality to the capital input. The model is an augmented version of Paul Romer's (1987) reformulation of the Solow model. Unlike Romer, however, we...

We characterize the entire set of linear equilibria of beauty contest games under general information structures. In particular, we focus on equilibria in which sentiments, that is self-fulfilling changes in beliefs that are orthogonal to fundamentals and exogenous noise, can drive aggregate...

This paper studies how financial information frictions can generate sentiment-driven fluctuations in asset prices and self-fulfilling business cycles. In our model economy, exuberant financial market sentiments of high output and high demand for capital increase the price of capital, which...

We formalize the Keynesian insight that aggregate demand driven by sentiments can generate output fluctuations under rational expectations. When production decisions must be made under imperfect information about demand, optimal decisions based on sentiments can generate stochastic...