We specify an empirical framework to detect the effects of official intervention on real exchange rate dynamics. Using data for 27 advanced and emerging market economies, we find evidence that interventions are a near-universal practice; almost all countries intervene when real exchange rates...

In the past 15 years, incentive-based environmental policy instruments, such as pollution taxes and tradeable pollution permits, have become an important supplement to tradition command-and-control instruments in Europe and the U.S. This paper proposes a positive theory of environmental...

In a number of evolutionary models the presence of mutations, or random components of choice, serve to refine predictions of long-run behavior. We analyze the effects of mutation rates that vary because of the presence of imitation. A full characterization of long-run outcomes is provided for...

We study the efficient allocation of spending and taxation authority in a federation in which federal politicians are exposed to electoral uncertainty. We show that centralization may, but need not, result in a loss of electoral accountability. We identify an important asymmetry between positive...

Consider an exchange economy with multiple competitive equilibria. Agents know the set of equilibria, but not which will be selected. To insure against unfavorable equilibrium outcomes, they trade on markets for commodities contingent on the equilibrium price vector. Such price-contingent...