Recent evidence suggests that consumption rises in response to an increase in government spending. That finding cannot be easily reconciled with existing optimizing business cycle models. We extend the standard new Keynesian model to allow for the presence of rule-of-thumb consumers. We show how...

We examine the role of expectations in the Great Moderation episode. We derive theoretical restrictions in a New-Keynesian model and test them using measures of expectations obtained from survey data, the Greenbook and bond markets. Expectations explain the dynamics of inflation and of interest...

I analyze the effects of an increase in government purchases financed entirely through seignorage, in both a classical and a New Keynesian framework, and compare them with those resulting from a more conventional debt-financed stimulus. My findings point to the importance of nominal rigidities...

We examine monetary policy in the Euro area from both theoretical and empirical perspectives. We discuss what theory tells us the strategy of Central banks should be and contrasts it with the one employed by the ECB. We review accomplishments (and failures) of monetary policy in the Euro area...

In this paper we study the macroeconomic effects of an inflow of low-skilled workers into an economy where there is capital accumulation and two types of agents. We find that there are substantial dynamic effects following unexpected migrations with adjustments that resemble those triggered by a...

We examine the dynamics of US output and inflation using a structural time varying coefficient VAR. We show that there are changes in the volatility of both variables and in the persistence of inflation. Technology shocks explain changes in output volatility, while a combination of technology,...

We construct and calibrate a general equilibrium business cycle model with unemployment and precautionary saving. We compute the cost of business cycles and locate the optimum in a set of simple cyclical fiscal policies. Our economy exhibits productivity shocks, giving firms an incentive to hire...

We examine the dynamics of output growth and inflation in the US, Euro area and UK using a structural time varying coefficient VAR. There are important similarities in structural inflation dynamics across countries; output growth dynamics differ. Swings in the magnitude of inflation and output...

We investigate identifiability issues in DSGE models and their consequences for parameter estimation and model evaluation when the objective function measures the distance between estimated and model impulse responses. We show that observational equivalence, partial and weak identification...

I discuss the identifiability of a structural New Keynesian Phillips curve when it is embedded in a small scale dynamic stochastic general equilibrium model. Identification problems emerge because not all the structural parameters are recoverable from the semi-structural ones and because the...