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...

Using a sample of Harvard undergraduates, we analyze trust and social capital in two experiments. Trusting behavior and trustworthiness rise with social connection; differences in race and nationality reduce the level of trustworthiness. Certain individuals appear to be persistently more...

Policy rules that are consistent with inflation targeting are examined in a small macroeconomic model of the US economy. We compare the properties and outcomes of explicit instrument rules' as well as targeting rules.' The latter, which imply implicit instrument rules, may be closer to actual...