Because inputs are scarce, marginal cost should be an increasing function of output. Without changes in this real marginal cost schedule, aggregate output can vary if and only if the markup of price over marginal cost varies. In this review, we discuss the extent to which observed fluctuations...

This paper illustrates how fluctuations in aggregate economic activity can result from many small, independent shocks to individual sectors. The effects of the small independent shocks fail to cancel in the aggregate due to the presence of two non-standard assumptions: local interaction between...

The paper presents an intertemporal general equilibrium model with rationing in the product market, in which stationary sunspot equilibria are shown to exist, indicating the possibility of fluctuations in economic activity simply due to self-fulfilling variations in economic agents'...

The massive expansion of central-bank balance sheets in response to recent crises raises important questions about the effects of such "quantitative easing" policies, both their effects on financial conditions and on aggregate demand (the intended effects of the policies), and their possible...

A number of commentators have argued that the desirability of inflation targeting as a framework for monetary policy analysis should be reconsidered in light of the global financial crisis, on the ground that it requires neglect of the implications of monetary policy for financial stability....