Abstract:
Childhood lead exposure can lead to psychological traits that are strongly associated with aggressive and criminal behavior. In the late 1970s in the United States, lead was removed from gasoline under the Clean Air Act. I use the state-specific reductions in lead exposure that resulted from this removal to identify the effect of childhood lead exposure on crime rates. The elasticity of violent crime with respect to childhood lead exposure is estimated to be 0.8, and this result is robust to numerous sensitivity tests. Mixed evidence supports an effect of lead exposure on murder rates, and little evidence indicates an effect of lead on property crime. Overall, I find that the reduction in childhood lead exposure in the late 1970s and early 1980s was responsible for significant declines in violent crime in the 1990s and may cause further declines in the future. Moreover, the social value of the reductions in violent crime far exceeds the cost of the removal of lead from gasoline.
Abstract:
It is well known that exposure to lead has numerous adverse effects on behavior and development, but little work to date has examined the cumulative lifetime effect of such exposure on aspects of behavior. In this paper, I use data on a cohort of children from the NLSY to investigate the effect of early childhood lead exposure on behavior problems from childhood through early adulthood. I find large negative consequences of early childhood lead exposure, in the form of an unfolding series of adverse behavioral outcomes ranging from oppositional behavior and impulsivity as a child, to bullying as a pre-teen, to pregnancy as a teen, to criminal behavior as a young adult. Estimated elasticities of these behaviors with respect to lead range between 0.2 and 2.0, and are robust to specification tests. This evidence suggests that, by increasing impulsivity and aggression, even moderate exposure to lead in early childhood can have substantial and persistent adverse effects on individual behavior. Moreover, such moderate exposure was the norm for all residents of the United States born between the 1950s and the early 1980s.
Abstract:
Lead exposure has been linked to infertility, miscarriage, stillbirth, pre-term delivery,
low birth weight, and infant mortality. This paper uses the sharp reductions in lead exposure
resulting from the removal of lead from gasoline under the Clean Air Act to identify how
prenatal lead exposure affects these reproductive outcomes. I find that prenatal lead exposure
increases infant mortality and the likelihood of low birth weight. The complete phaseout of
leaded gasoline is associated with 3-4% reductions in infant mortality and low birth weight.
I identify these effects using state-level variation in gasoline lead consumption and detailed
data on nearly all births in the United States between 1975 and 1985. I conclude that even
moderate levels of prenatal lead exposure can significantly harm fetal and infant health and
that the removal of lead from gasoline has produced small but significant benefits for
reproductive and infant health.
Abstract:
This paper analyzes how the imperfectly competitive market for Obstetricians and Gynecologists
(OB/GYNs) clears in the face of an excess demand for female OB/GYNs. This excess demand
results from the convergence of three factors: i) all OB/GYN patients are women, ii) many
women prefer to be treated by a female OB/GYN, iii) only a small portion of OB/GYNs are female.
The paper finds that both money and non-money prices adjust: female OB/GYNs charge higher fees
and also have longer waiting times. Furthermore, these effects are mediated by institutional
structure: in contract settings in which money prices are rigid (i.e. managed care), waiting
times are more likely to adjust, and in settings in which money prices are more flexible,
the reverse occurs.
Abstract:
In U.S. Census data from 1940 to 1990, a large number of women appear to be
earning unbelievably low wages. While these outliers are customarily dropped
from the data when performing economic analysis, I find that this is an inappropriate
strategy. From 1940 to 1960, many women appear to have actually earned such
extremely low wages. These women were primarily full-year full-time black
domestic workers. They represent a significant disadvantaged population that
experienced major improvement in the latter half of this century. The paper
argues that this group should not be excluded from the history of American
inequality.
Abstract:
The financial aid system imposes an implicit asset tax that is prevalent and
substantial. Facing this tax, rational families should reduce their total
assets and shelter assets in protected categories. I find that the tax induces
a 7% reduction in total assets, a result in line with the literature. Furthermore,
I find evidence that families reallocate assets into sheltered retirement
accounts. The paper provides further evidence that the financial aid tax reduces
asset accumulation and prompts a reconsideration of the simple “higher
tax, lower assets” story. It provides the first evidence that families
may be engaging in a rational reallocation of their asset portfolio.
Department of
Economics
307 Converse Hall — Amherst College
— Amherst, MA
(413) 542.8517— jwreyes AT amherst.edu