Output Fluctuations Persistence : Do Cyclical Shocks Matter?

The aim of this paper is to identify the different sources of persistence of output fluctuations. We propose an unobserved components model that allows us to decompose GDP series into a trend component and a cyclical component. We let the drift of the trend component to switch between different regimes according to a first-order Markov process. To calculate an appropriate p-value for a test of linearity we propose a bootstrap procedure, which allows for general forms of heteroskedasticity. The performance of the bootstrap is checked by means of a Monte Carlo simulation. Our study concerns the U.S. As suggested by the Endogenous Growth theory, cyclical shocks appear to play an important role on the observed persistence of output. We argue that the traditional explanation of persistence, which is related to Real Business Cycle models with exogenous productivity, is not consistent with our data. We also find that the majority of business cycle fluctuations in the U.S. are due to real shocks