Policy Rule Coefficients Driven by Latent Factors: Monetary and Fiscal Policy Interactions in an Endowment Economy

In this paper I formulate, solve and estimate an endowment version of a macroeconomic dynamic stochastic general equilibrium model with monetary and fiscal policy rules whose coefficients are time-varying and contemporaneously correlated. The aim of the paper is to identify from data the interactions between monetary and fiscal policies that have prevailed in the U.S. economy. The monetary authority uses a Taylor rule and the fiscal authority uses a rule in which taxes respond to lagged debt deviations. Policy rule coefficients are modeled as logistic functions of stationary correlated latent factors, introducing long-run interactions between monetary and fiscal policies. There are three main findings of the paper: First, monetary policy has reacted strongly to inflation deviations along, almost, the entire analyzed period, with a loose policy only during the periods 1979:1-1981:3 and 2008:4-2009:2. Second, regimes under which a determinacy condition is in place occur 54.25% of the time, while regimes with exploding local dynamics occur 45.34% of the time, and there is an association between the duration of these unstable regimes and the volatility of inflation. Third, tightening monetary policy in terms of increasing the reaction of the central bank with respect to inflation deviations, given the situation of the economy in the third quarter of 2010, implies an increase in inflation of the order of 3%.