Should We Use Linearized Models To Calculate Fiscal Multipliers?
We calculate the magnitude of the government consumption multiplier in linearized and nonlinear solutions of a New Keynesian model at the zero lower bound. Importantly, the model is amended with real rigidities to simultaneously account for the macroeconomic evidence of a low Phillips curve slope and the microeconomic evidence of frequent price changes. We show that the nonlinear solution is associated with a much smaller multiplier than the linearized solution in long-lived liquidity traps, and pin down the key features in the model which account for the di¤erence. Our results caution against the common practice of using linearized models to calculate scal multipliers in long-lived liquidity traps.