Empirical studies of firms within industries consistently report substantial heterogeneity in measures of performance such as size and productivity. This paper explores the consequences of joint heterogeneity on the supply side (sellers) and the demand side (buyers) in international trade using...

Large fluctuations in energy prices have been a distinguishing characteristic of the U.S. economy since the 1970s. Turmoil in the Middle East, rising energy prices in the U.S. and evidence of global warming recently have reignited interest in the link between energy prices and economic...

Several policymakers and economists have proposed the adoption of a carbon tax in the United States. It is widely recognized that such a tax in practice must take the form of a tax on the consumption of energy products such as gasoline. Although a large existing literature examines the...

The conventional diagnosis of Germany’s poor economic performance focuses on supply-side weaknesses and the need for more vigorous reforms to make low-skill labour markets more flexible. We question this on both theoretical and empirical grounds. In an extended version of a New Keynesian model...

This paper provides a brief, non-technical survey of the major theories about why people remain unemployed. The aim is to provide a macroeconomic perspective on the microeconomic problem of why people don't find work. The first section deals with market-clearing theories: the natural rate...

We present a static model of aggregate demand and unemployment. The economy has a nonproduced good, a produced good, and labor. Product and labor markets have matching frictions. A general equilibrium is a set of prices, market tightnesses, and quantities such that buyers and sellers optimize...

This paper presents a simple macroeconomic model where government spending affects aggregate demand directly and indirectly, through an expectational channel. Prices are fully flexible and the model is static, so intertemporal issues play no role. There are three important elements in the model:...

Periods of low household wealth in United States macroeconomic history have also been periods of high business cycle volatility. This paper develops a simple model that can exhibit self-fulfilling fluctuations in the expected path for unemployment. The novel feature is that the scope for...

We enrich workhorse macroeconomic models with a mechanism that proxies strategic uncertainty and that manifests itself as waves of optimism and pessimism about the short-term economic outlook. We interpret this mechanism as variation in "confidence" and show that it helps account for many...