This paper examines the effect of waterborne lead exposure on infant mortality in American cities over the period 1900 to 1920. Variation across cities in water acidity and the types of service pipes, which together determined the extent of lead exposure, identifies the effects of lead on infant...

This paper examines how the fertility of enslaved women was affected by the promise of freedom. Exploiting geographic variation in the effect of the Fugitive Slave Law of 1850, I demonstrate a negative correlation between fertility and the distance to freedom. This negative correlation is...

I investigate the importance of the match between teachers and schools for student achievement. I show that teacher effectiveness increases after a move to a different school and estimate teacher-school match effects. Match quality explains away a quarter of and has two-thirds the explanatory...

Standard job search theory assumes that unemployed individuals have perfect information about the effect of their search effort on the job offer arrival rate. We present an alternative model that assumes that each individual has a subjective belief about the impact of her search effort on the...

Despite the prevalence of R&D support programs, evaluation studies based on explicit differences in support allocation are rare. In this paper, the identification of the causal effect of R&D support on company performance is based on geographic variation in government funding arising from a...

We derive testable implications of instrument validity in just identified treatment effect models with endogeneity and consider several tests. The identifying assumptions of the local average treatment effect allow us to both point identify and bound the mean potential outcomes of the always...

Suppose that all people in the world are allocated only two characteristics over which they have (almost) no control: country of residence and income distribution within that country. Assume further that there is no migration. We show that more than one-half of variability in income of world...

We estimate the impact of incentive strength on achievement under a group-based teacher incentive pay program. The system provides variation in the share of students in a subject-grade that a teacher instructs, which proxies for incentive strength. We find that achievement on incentivized exams,...