We estimate the effect of government spending shocks on the US economy with a time-varying parameter vector autoregression. The recent Great Recession period appears to be characterized by uniquely large impulse responses of output to fiscal shocks. Moreover, the particularity of this period is...

This paper proposes a novel approach to introduce time-variation in structural parameters of DSGE models. Structural parameters are allowed to evolve over time via an observation-driven updating equation. The estimation of the resulting DSGE model can be easily performed by maximum likelihood...