小型开放经济体政府支出的最优规模与构成

摘要

We study optimal fiscal policy in a small open economy within a currency union subject to downward nominal wage rigidity. Government spending is divided between public consumption and productive public investment, with investment accumulating into public capital subject to time-to-build. We characterize the Ramsey allocation when the policymaker jointly chooses consumption taxes, public consumption, and public investment. Fiscal instruments operate through distinct but complementary margins: consumption taxes mitigate unemployment distortions when wage rigidity binds, while spending composition provides an additional intertemporal stabilization margin. In particular, state contingent public investment reallocates non-tradable resources over time, smoothing private consumption and attenuating relative price fluctuations with limited contemporaneous distortions. Calibrating the model to France, we find that coordinated fiscal policy substantially reduces unemployment risk and generates measurable welfare gains relative to regimes that rely only on taxes or keep government spending composition fixed. The results are robust across country re-calibrations for Greece, Italy, and Spain, as well as in extensions with government production, alternative time-to-build horizons, public capital adjustment costs, preference parameters, wage rigidity, and bond holding costs.