Historically, urban growth required enough development to grow and transport significant agricultural surpluses or a government effective enough to build an empire. But there has been an explosion of poor mega-cities over the last thirty years. A simple urban model illustrates that in closed...

We investigate optimal consumption, asset accumulation and portfolio decisions in a realistically calibrated life-cycle model with flexible labor supply. Our framework allows for wage rate uncertainly, variable labor supply, social security benefits and portfolio choice over safe bonds and risky...

Fiscal policy in the U.S. and other countries renders intertemporal budgets non-differentiable, nonconvex, and discontinuous. Consequently, assessing work and saving responses to policy requires global optimization. This paper develops the Global Life-Cycle Optimizer (GLO), a stochastic...