This paper provides general and empirically implementable sufficient statistics formulas for optimal nonlinear tax systems in the presence of across-income heterogeneity in preferences, inheritances, income-shifting capabilities, and other sources. We study unrestricted tax systems on income and...

This paper introduces an index of tax optimality that measures the distance of a current tax structure from the optimal tax structure in the presence of public goods. In doing so, we derive a [0, 1] number that reveals immediately how far the current tax configuration is from the optimal one...

What is an optimal or a sustainable external debt - for a country, region or sector? How should one monitor and evaluate debt to preclude a crisis? We use stochastic optimal control/dynamic programming to derive an optimal debt. The deviation of the actual from the optimal will serve as a...

We use stochastic optimal control-dynamic programming (DP) to derive the optimal foreign debt/net worth, consumption/net worth, current account/net worth, and endogenous growth rate in an open economy. Unlike the literature that uses an Intertemporal Budget Constraint (IBC) or the Maximum...

The recent financial crises, especially the debt crisis in Asia, have led to questions su ch as: what are their causes, what is an excessive debt and how vulnerable is an economy to external shocks? We develop an economic model of international finance and debt based upon two sources of...

We estimate a three-region (DE-REA-RoW) structural macroeconomic model, and we provide a counterfactual on how nominal exchange rate flexibility would have affected the German trade balance (TB) by simulating the shocks of the estimated model under a counterfactual flexible exchange rate regime....

Bilateral trade balances often play an important role in the international trade policy debate. Academic economists understand that they are misleading indicators of competitiveness and of the gains from trade. However, they also recognize their political relevance, calling for accurate...