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...

Myopia is increasingly believed to be a significant determinant of behavior and also plays a central role in justifications for social security and policies toward the taxation of capital. It is important, however, to account for labor supply effects, particularly in light of the preexisting...