Essays on optimal monetary and fiscal policy in dynamic economies

We study optimal fiscal and monetary policy in the context of dynamic, neoclassical general equilibrium models with a representative agent.; The first paper studies the welfare effects of feasible tax reforms in a Uzawa-Lucas model with money, cash-credit goods and distorting taxes. We perform a series of numeric exercises where a tax on capital income is eliminated and replaced either by higher taxes on labor income or money holdings. If the analysis is restricted to the balanced-growth path, we find sizable welfare gains of eliminating such tax regardless of how lost revenue is raised. Once transitional dynamic effects are considered, such gains are significantly reduced when revenue is raised through labor income taxes and become negative when taxes on money holdings are used. Monetary distortions on credit goods are mostly responsible for the last result.; In the second paper, we present a model with a general cash-in-advance constraint and distorting taxes. The model is used to find the optimal monetary policy at the steady state and estimate the welfare gain of adopting such a policy. We show that the optimal policy is dictated by the Friedman rule if lump-sum taxes are available but it becomes indeterminate if distorting taxes are used instead. In general, numerically we find a small welfare gain from following the Friedman rule but a small welfare loss in the second case. For each situation, welfare estimates are very sensitive to changes in the interest-elasticity of money.; The final paper studies optimal taxation policy in a model where the consumer exhibits time-inconsistent preferences but the planner does not. Steady-state analysis shows that the optimal tax on capital income is non-positive whereas the optimal tax on labor income is zero. We solve numerically for the equilibrium path of optimal taxes off the steady state and find that the subsidy to capital extends through most of the transition period. We also find that more impatient economies face larger subsidies to capital. In those cases, the planner optimally chooses to impose the burden of taxation on labor income but only at the initial period, even though labor is elastically supplied.