Aggregate and sectoral comovement are central features of business cycles, so the ability to generate comovement is a natural litmus test for macroeconomic models. But it is a test that most models fail. We propose a unified model that generates aggregate and sectoral comovement in response to contemporaneous and news shocks about fundamentals. The fundamentals that we consider are aggregate and sectoral total factor productivity shocks as well as investment-specific technical change. The model has three key elements: variable capital utilization, adjustment costs to investment, and preferences that allow us to parameterize the strength of short-run wealth effects on the labor supply.

Recent estimates of the potential growth effects of tax reform vary wildly, ranging from zero to eight percentage points. Using an endogenous growth model, the authors assess which model features and parameter values are important for determining the quantitative impact of tax reform. The quantitative estimates in several recent papers are compared with each other and with some of the evidence from U.S. experience. The authors find that Robert Lucas's conclusion, that tax reform would have little or no impact on the U.S. growth rate, is theoretically robust and consistent with the evidence.

This paper studies how the impact of monetary policy depends on the distribution of savings from refinancing mortgages. We show that the efficacy of monetary policy is state dependent, varying in a systematic way with the pool of potential savings from refinancing. We construct a quantitative dynamic life-cycle model that accounts for our findings and use it to study how the response of consumption to a change in mortgage rates depends on the distribution of savings from refinancing. These effects are strongly state dependent. We also use the model to study the impact of a long period of low interest rates on the potency of monetary policy. We find that this potency is substantially reduced both during the period and for a substantial amount of time after interest rates renormalize.

We argue that the government-spending multiplier can be much larger than one when the zero lower bound on the nominal interest rate binds. The larger is the fraction of government spending that occurs while the nominal interest rate is zero, the larger is the value of the multiplier. After providing intuition for these results, we investigate the size of the multiplier in a dynamic, stochastic, general equilibrium model. In this model the multiplier e�ect is substantially larger than one when the zero bound binds. Our model is consistent with the behavior of key macro aggregates during the recent financial crisis. We thank the editor, Monika Piazzesi, Rob Shimer, and two anonymous referees for their

In this article, we provide direct evidence on the behaviour of markups in the retail sector across space and time. Markups are measured using gross margins. We consider three levels of aggregation: the retail sector as a whole, the firm, and the product level. We find that: (1) markups are relatively stable over time and mildly procyclical; (2) there is a large regional dispersion in markups; (3) there is a positive cross-sectional correlation between local income and local markups; and (4) differences in markups across regions result from differences in the assortment of goods sold in different regions, not from deviations from uniform pricing. We propose a simple model consistent with these facts.

We study the properties of the carry trade, a currency speculation strategy in which an investor borrows low-interest-rate currencies and lends high-interest-rate currencies. This strategy generates payoffs that are on average large and uncorrelated with traditional risk factors. We argue that these payoffs reflect a peso problem. The underlying peso event features high values of the stochastic discount factor rather than very large negative payoffs.

We propose a model of sovereign debt in which countries vary in their level of financial development, defined as the extent to which they can issue debt denominated in domestic currency in international capital markets. We show that low levels of financial development generate the “debt intolerance” phenomenon that plagues emerging markets: it reduces overall debt capacity, increases credit spreads, and limits the country's ability to smooth consumption.

This paper argues that a principal cause of the 1997 Asian currency crisis was large prospective deficits associated with implicit bailout guarantees to failing banking systems. The expectation that these future deficits would be at least partially financed by seigniorage revenues or an inflation tax on outstanding nominal debt led to a collapse of the fixed exchange rate regimes in Asia. We articulate this view using a simple model whose key feature is that a speculative attack is inevitable once the present value of future government deficits rises. We present empirical evidence in support of the key assumptions underlying our interpretation of the crisis.

This paper investigates the sensitivity of Solow residual based measures of technology shocks to labor-hoarding behavior. Using a structural model of labor hoarding and the identifying restriction that innovations to technology shocks are orthogonal to innovations in government consumption, the authors estimate the fraction of the variability of the Solow residual that is due to technology shocks. Their results support the view that a significant proportion of movements in the Solow residual are artifa cts of labor-hoarding behavior. Specifically, the authors estimate that the variance of innovations to technology is roughly 50 percent less than that implied by standard real business cycle models.

We use new, comprehensive micro data on oil fields to build and estimate a structural model of the oil industry embedded in a general equilibrium model of the world economy. In the model, firms that belong to Organization of the Petroleum Exporting Countries (OPEC) act as a cartel. The remaining firms are a competitive fringe. We use the model to study the macroeconomic impact of the advent of fracking. Fracking weakens the OPEC cartel, leading to a large long-run decline in oil prices. Fracking also reduces the volatility of oil prices in the long run because fracking firms can respond more quickly to changes in oil demand.