We analyze a large-scale trial of an early-childhood education program targeting premature, low-birthweight children, thereby oversampling twins. We find that failing to account for this oversampling obscures the program's benefits. Among singletons, treatment increased childcare hours and...

Using two comprehensive datasets on population of cities (1800-2000) and metropolitan areas (1960-2000) for a large set of countries, I present three new empirical facts about the evolution of city growth. First, the distribution of cities growth rates is skewed to the right in most countries...

Several studies have documented a negative relationship between democracy and volatility. The latter is usually measured at high frequency - as the standard deviation of annual GDP growth rates. On the other hand, growth researchers have recently focused on the medium term and documented...

This paper uses aggregate data from the International Labor Organization and microeconomic data from the European Values Study to quantify gender gaps in entrepreneurship, distinguishing between gender gaps in employership and in self‐employment, and study their main empirical determinants....