Technological change, from the advent of robots to expanded trade opportunities, tends to create winners and losers. How should government policy respond? And how should the overall welfare impact of technological change on society be valued? We provide a general theory of optimal technology...

We study the positive (not normative) effect of a permanent import tariff on trade deficits. We consider a two-period trade model with general preferences and technology. We first develop an aggregation result showing one can work with induced preferences over aggregate imports and exports. This...

We present a theory of Keynesian supply shocks: supply shocks that trigger changes in aggregate demand larger than the shocks themselves. We argue that the economic shocks associated to the COVID-19 epidemic--shutdowns, layoffs, and firm exits--may have this feature. In one-sector economies...

This paper isolates the role of conflict or disagreement on inflation in two ways. In the first part of the paper, we present a stylized model, kept purposefully away from traditional macro models. Inflation arises despite the complete absence of money, credit, interest rates, production, and...

This note isolates an overlooked economic force for the Ruble to appreciate in response to international sanctions limiting exports to Russia. The economic intuition is that when Russians are unable to buy the mix of foreign goods they wish, then foreign goods becomes less attractive, increasing...

This paper develops a simple theory of capital controls as dynamic terms-of-trade manipulation. We study an infinite horizon endowment economy with two countries. One country chooses taxes on international capital flows in order to maximize the welfare of its representative agent, while the...

What is the effect of higher expectations of future inflation on current inflation? I compute this passthrough for a series of canonical firm-pricing models, but allowing for arbitrary (non-rational) expectations. In the Calvo model, the expectational-passthrough can be made arbitrarily close to...

The theory of comparative advantage is at the core of neoclassical trade theory. Yet we know little about its implications for how nations should conduct their trade policy. For example, should import sectors with weaker comparative advantage be protected more? Conversely, should export sectors...

What circumstances or policies leave sovereign borrowers at the mercy of self-fulfilling increases in interest rates? To answer this question, we study the dynamics of debt and interest rates in a model where default is driven by insolvency. Fiscal deficits and surpluses are subject to shocks...

How does market concentration affect the potency of monetary policy? The ubiquitous monopolistic-competition framework is silent on this issue. To tackle this question we build a model with heterogeneous oligopolistic sectors. In each sector, a finite number of firms play a Bertrand dynamic game...