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...

Alfred Marshall argues that industrial agglomerations exist in part because individuals can" learn skills from each other when they live and work in close proximity to one another. An" increasing amount of evidence suggests that the informational role of cities is a primary reason for" their...

We study how the use of judgement or “add-factors” in macroeconomic forecasting may disturb the set of equilibrium outcomes when agents learn using recursive methods. We isolate conditions under which new phenomena, which we call exuberance equilibria, can exist in standard macroeconomic...

We examine global dynamics under infinite-horizon learning in New Keynesian models where the interest-rate rule is subject to the zero lower bound. As in Evans, Guse and Honkapohja (2008), the intended steady state is locally but not globally stable. Unstable deflationary paths emerge after...

There are many possible ways of reforming the Government-Sponsored Enterprises that insure mortgages against default, including a purely public option, complete privatization or a hybrid model with private firms and public catastrophic insurance. If the government is sufficiently capable and...

Why are public-sector workers so heavily compensated with pensions and other non-pecuniary benefits? In this paper, we present a political economy model of shrouded compensation in which politicians compete for taxpayers' and public employees' votes by promising compensation packages, but some...

Research on entrepreneurship often examines the local dimensions of new business formation. The local environment influences the choices of entrepreneurs; entrepreneurial success influences the local economy. Yet modern urban economics has paid relatively little attention to entrepreneurs. This...

Cities generate negative, as well as positive, externalities; addressing those externalities requires both infrastructure and institutions. Providing clean water and removing refuse requires water and sewer pipes, but the urban poor are often unwilling to pay for the costs of that piping....