We construct a matrix showing the share of the year 2000 population in every country that is descended from people in different source countries in the year 1500. Using this matrix, we analyze how post-1500 migration has influenced the level of GDP per capita and within-country income inequality...

We study the distribution of economic activity, as proxied by lights at night, across 250,000 grid cells of average area 560 square kilometers. We first document that nearly half of the variation can be explained by a parsimonious set of physical geography attributes. A full set of country...

We analyze the setting of monetary and nonmonetary policies in monetary unions. We show that in these unions a time inconsistency problem in monetary policy leads to a novel type of free- rider problem in the setting of nonmonetary policies, such as labor market policy, fiscal policy, and bank...

The desirability of fiscal constraints in monetary unions depends critically on whether the monetary authority can commit to follow its policies. If it can commit, then debt constraints can only impose costs. If it cannot commit, then fiscal policy has a free-rider problem, and debt constraints...

We present a model of growth and technology transfer based on the idea that technologies are specific to particular combinations of inputs. We argue that this model is more realistic than the usual specification, in which an improvement in any technique for producing a given good improves all...

This paper examines a novel mechanism linking fertility and growth. Household fertility is determined by relative wages of women and men. Increasing women's wages reduces fertility by raising the cost of children relatively more than household income. Lower fertility raises the level of capital...

We provide an introduction to optimal fiscal and monetary policy using the primal approach to optimal taxation. We use this approach to address how fiscal and monetary policy should be set over the long run and over the business cycle. We find four substantive lessons for policymaking: Capital...