Publications

This study re-evaluates the macroeconomic impact of monetary policy shocks in the United States using the proxy-SVAR approach of Gertler and Karadi (American Economic Journal: Macroeconomics, 2015, 7, 44–76). Despite increased credit costs and the presence of the credit channel, our analysis reveals modest effects on economic activity post-mid-1980s. This robust finding holds across various inference methods and sample considerations. A counterfactual analysis within the framework of Bernanke, Gertler, and Gilchrist (1999, Handbook of Macroeconomics, Elsevier) suggests that a stronger response to inflation in monetary policy execution may explain the subdued impact of shocks, offering valuable insights for policy refinement and understanding the dynamics of economic activity. 

Is the typical specification of the Euler equation for investment employed in dynamic stochastic general equilibrium (DSGE) models consistent with aggregate macro data? The answer is yes using state-of-the-art econometric methods that are robust to weak instruments and exploit information in possible structural changes. Unfortunately, however, there is very little information about the values of the parameters in aggregate data because investment is unresponsive to changes in capital utilization and the real interest rate. Bayesian estimation using fully specified DSGE models is more accurate due to both informative priors and cross-equation restrictions.

We examine the effects of three facets of monetary policy in Australia using high-frequency yield changes around the Reserve Bank of Australia's announcements: current policy, signalling/forward guidance and changes in premia. Shocks to current policy have similar effects to those identified using conventional approaches, but the effects of signalling and premia shocks are imprecisely estimated. Still, the approach provides the following evidence: forward guidance shocks raised future rate expectations in the mid-2010s as the Reserve Bank of Australia highlighted housing risks; COVID-era policy mainly affected term premia, unlike pre-COVID policy; shocks to the expected path of rates are predictable, suggesting markets misunderstand the RBA's reaction to data. 

We estimate a medium-scale model with and without rule-of-thumb consumers over the pre-Volcker and the Great Moderation periods, allowing for indeterminacy. Passive monetary policy and sunspot fluctuations characterize the pre-Volcker period for both models. In both sub-samples, the estimated fraction of rule-of-thumb consumers is low, such that the models are empirically almost equivalent; they yield very similar impulse response functions, variance and historical decompositions. We conclude that rule-of-thumb consumers are irrelevant to explain aggregate U.S. business cycle fluctuations.

The asymptotic distributions of the recursive out-of-sample forecast accuracy test statistics depend on stochastic integrals of Brownian motion when the models under comparison are nested. This often complicates their implementation in practice because the computation of their asymptotic critical values is burdensome. Hansen and Timmermann (2015, Econometrica) propose a Wald approximation of the commonly used recursive F-statistic and provide a simple characterization of the exact density of its asymptotic distribution. However, this characterization holds only when the larger model has one extra predictor or the forecast errors are homoscedastic. No such closed-form characterization is readily available when the nesting involves more than one predictor and heteroscedasticity or serial correlation is present. We first show through Monte Carlo experiments that both the recursive F-test and its Wald approximation have poor finite-sample properties, especially when the forecast horizon is greater than one and forecast errors exhibit serial correlation. We then propose a hybrid bootstrap method consisting of a moving block bootstrap and a residual-based bootstrap for both statistics and establish its validity. Simulations show that the hybrid bootstrap has good finite-sample performance, even in multi-step ahead forecasts with more than one predictor, heteroscedastic or autocorrelated forecast errors. The bootstrap method is illustrated on forecasting core inflation and GDP growth.

Existing empirical evidence on the Euler equation based on closed economy models suggests low responsiveness of aggregate consumption to changes in interest rates. We incorporate open economy features and consider extensions that include habit formation and hand-to-mouth consumers. For several open economies and applying econometric methods that are robust to weak instruments and structural changes, we continue to find low values for the elasticity of intertemporal substitution, implying a small effect of real interest rate changes on aggregate income. In some countries, structural changes are informative for identification, but otherwise aggregate data provide limited information to learn about IS-curve specifications.

This paper estimates a New Keynesian model with trend inflation and contrasts Taylor rules featuring fixed versus time-varying inflation target. The estimation is conducted over the Great Inflation and the Great Moderation periods, while allowing for indeterminacy. Time-varying inflation target empirically fits better and active monetary policy prevails in both periods, thereby ruling out sunspots as an explanation of the Great Inflation episode.

We estimate a time-varying parameter VAR (TVP-VAR) with stochastic volatility using U.S. data to study the effects of uncertainty shocks on inflation. We find the response of inflation to be negative in the post-WWII period. Our findings suggest that uncertainty shocks propagate like aggregate demand shocks and not like aggregate supply shocks.

The paper re-examines whether the Federal Reserve's monetary policy was a source of instability during the Great Inflation by estimating a sticky-price model with positive trend inflation, commodity price shocks and sluggish real wages. Our estimation provides empirical evidence for substantial wage-rigidity and finds that the Federal Reserve responded aggressively to inflation but negligibly to the output gap. In the presence of non-trivial real imperfections and well-identified commodity price-shocks, U.S. data prefers a determinate version of the New Keynesian model: monetary policy-induced indeterminacy and sunspots were not causes of macroeconomic instability during the pre-Volcker era. However, had the Federal Reserve in the Seventies followed the policy rule of the Volcker-Greenspan-Bernanke period, inflation volatility would have been lower by one third.

We study the time-varying effects of financial uncertainty shocks in the U.S. using a vector autoregression with drifting parameters and stochastic volatilities. We find negative effects of financial uncertainty shocks on real activity with both consumption and investment growth declining significantly and comoving along the entire sample. These effects remained fairly stable in the post-WWII period but the negative response of investment growth became more pronounced during the Zero Lower Bound episode. Our findings lend empirical support to theoretical frameworks that can successfully capture this macroeconomic comovement following an uncertainty shock. Remarkably, we find a limited role for financial uncertainty shocks during the Great Recession. 

This paper estimates a New Keynesian model of the U.S. economy over the period following the 2001 slump, a period for which the adequacy of monetary policy is intensely debated. We find that only when measuring inflation with core PCE does monetary policy appear to have been reasonable and sufficiently active to rule out indeterminacy. We then relax the assumption that inflation in the model is measured by a single indicator and re-formulate the artificial economy as a factor model where the theory's concept of inflation is the common factor to the empirical inflation series. CPI and PCE provide better indicators of the latent concept while core PCE is less informative. Finally, we estimate an economy that distinguishes between core and headline inflation rates. This model comfortably rules out indeterminacy.