Do scale economies contribute to our understanding of international trade? Do international trade flows encode information about the extent of scale economies? To answer these questions we examine the large class of general equilibrium theories that imply Helpman-Krugman variants of the Vanek...

We study optimal monetary policy during temporary supply contractions when aggregate demand has inertia and expansionary policy is constrained. In this environment, it is optimal to run the economy hot until supply recovers. Positive output gaps in the low-supply phase lessen the negative output...

We incorporate demand-side considerations in trade in a systematic but straightforward way. We do so by focusing on the role of inequality in the determination of trade flows and patterns. With nonhomothetic preferences, when countries are similar in all respects but asset inequality, we find...

We survey recent literature on the causes of the collapse in international trade during the 2008-2009 global recession. We argue that the evidence points to the collapse in aggregate expenditure, concentrated on trade-intensive durable goods, as the main driver of the trade collapse. Inventory...

This paper is part of a broader project that provides a microfoundation to the General Theory of J.M. Keynes. I call this project 'old Keynesian economics' to distinguish it from new-Keynesian economics, a theory that is based on the idea that to make sense of Keynes we must assume that prices...

An aggregate demand - aggregate supply framework is used to analyze the effects of Japanese monetary policy, 1973:1-1990:8. It is found that money supply shocks contribute relatively little to output variability over the sample as a whole. Nor do these shocks seem to be particularly marked...

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...

We construct a model to capture the Keynesian idea that production and employment decisions are based on expectations of aggregate demand driven by sentiments, and that realized demand follows from the production and employment decisions of firms. We cast the Keynesian idea into a simple model...