Are optimal monetary and fiscal policies time consistent in a monetary economy? Yes, but if and only if under commitment the Friedman rule of setting nominal interest rates to zero is optimal. This result is of applied interest because the Friedman rule is optimal for the standard preferences...

We make two comparisons relevant for the business cycle accounting approach. We show that in theory representing the investment wedge as a tax on investment is equivalent to representing this wedge as a tax on capital income as long as the probability distributions over this wedge in the two...

In the data, a large fraction of price changes are temporary. We provide a simple menu cost model which explicitly includes a motive for temporary price changes. We show that this simple model can account for the main regularities concerning temporary and permanent price changes. We use the...

This paper by Baxter and Kouparitsas is an ambitious attempt to explore which variables are robust in explaining the correlations of bilateral GDP between countries at business cycle frequencies. Most of the variables turned out to be fragile. The main contribution is to show that countries with...

We propose a simple method to help researchers develop quantitative models of economic fluctuations. The method rests on the insight that many models are equivalent to a prototype growth model with time-varying wedges which resemble productivity, labor and investment taxes, and government...

The classic explanation for the persistence and volatility of real exchange rates is that they are the result of nominal shocks in an economy with sticky goods prices. A key implication of this explanation is that if goods have differing degrees of price stickiness then relatively more sticky...

In the data, a sizable fraction of price changes are temporary price reductions referred to as sales. Existing models include no role for sales. Hence, when confronted with data in which a large fraction of price changes are sales related, the models must either exclude sales from the data or...

We ask what fraction of the variation in incomes across countries can be accounted for by investment distortions. In our neoclassical growth model the relative price of investment to consumption is a good measure of the distortions. Using data on relative prices we estimate a stochastic process...

The common approach to evaluating a model in the structural VAR literature is to compare the impulse responses from structural VARs run on the data to the theoretical impulse responses from the model. The Sims-Cogley-Nason approach instead compares the structural VARs run on the data to...