Anna
Aizer - Research
Research
Statement
Working
Papers
Education, Knowledge and
the Evolution of Disparities in Health (December 2011) with Laura
Stroud
We study
how advances in scientific knowledge affect the evolution of disparities in
health. Our focus is the 1964 Surgeon General Report on Smoking and Health –
the first widely publicized report of the negative effects of smoking on
health. Using an historical dataset that
includes the smoking habits of pregnant women 1959-1966, we find that
immediately after the 1964 Report, more educated mothers immediately reduced
their smoking as measured by both self-reports and serum cotinine
levels, while the less educated did not, and that the relative health of their
newborns likewise increased. We also
find strong peer effects in the response to information: after the 1964 report,
educated women surrounded by other educated women were more likely to reduce
smoking relative to those surrounded by less educated women. Over time, the education gradient in both
smoking and newborn health continued to increase, peaking in the 1980s and then
shrinking, eventually returning to initial levels. These results can explain why in an era of
great advancements in medical knowledge, health disparities may actually
increase, at least initially.
The Production of Child
Human Capital: Endowments, Investments and Fertility (March 2012)
with Flavio Cunha
We
study how endowments, investments and fertility interact to produce human
capital in childhood. First we explore the human capital production function.
Exploiting an exogenous source of investment, the launch of Head Start in 1966,
to identify the impact of investments (preschool) on child human capital (IQ),
we find strong evidence of complementarity between investments
and early human capital as evidenced by greater gains from preschool on the IQ
of those with the highest initial human capital. Second, because this complementarity generates incentives for parents to invest
in children with higher initial levels of human capital, we explore how
investments respond to child endowments and find that they are reinforcing.
Third, the degree of reinforcement increases with family size. Thus, in
addition to the tradeoff in quantity and average quality, an increase in
quantity also leads to greater variation in quality, due to both greater
variation in endowments (from higher fertility) and greater reinforcing investments.
Finally, we show that our findings are replicated by a quantity-quality
tradeoff model in which children are heterogeneous with respect to their
endowment and parental preferences feature weak complementarity
between quality and quantity as well as moderate aversion to inequality in the
human capital of children.
Maternal Stress and Child
Well-Being: Evidence from Siblings (April 2009)
with Laura Stroud and Stephen Buka
We study how maternal stress affects child outcomes. We find that in-utero exposure to elevated levels of the stress hormone cortisol negatively affects the cognition, health and
educational attainment of offspring.
These findings are based on comparisons between siblings to control for
unobserved differences between mothers that could bias estimates. Our results
are consistent with recent experimental results in the neuro-biological
literature linking exogenous exposure to coritsol in-utero with reduced growth in the hippocampal
region of the brain and declines in offspring cognitive, behavioral and motor
development. Moreover, we find that poor
mothers have both higher average levels of cortisol
and greater variability, suggesting that prenatal stress may play an important
role in explaining why relatively few children born into poverty are able to
escape it as adults.
Peer Effects, Institutions and
Human Capital Accumulation: The Externalities of ADD (April 2009)
Recent
work shows that peers affect student achievement, but the mechanisms are not
well understood. I show that peer behavior is an important mechanism, perhaps
more so than ability, by exploiting exogenous timing in diagnosis/treatment of
ADD among peers that improves peer behavior while holding peer achievement
constant. Improvements in peer behavior
increase student achievement. Moreover,
resources mitigate the negative effects of peer behavior. These findings imply
that the optimal response in the presence of peer effects is not necessarily to
reorganize classrooms. Rather, existing institutions can modify peer effects by
improving behavior and/or mitigating the impact of poor behavior.
Published/Forthcoming
Papers
The Gender Wage Gap and Domestic
Violence American Economic Review (2010),
100(4): 1847-59.
Three quarters of all violence against women is
perpetrated by domestic partners. This study exploits exogenous changes in the
demand for labor in female-dominated industries to estimate the impact of the male-female
wage gap on domestic violence. Decreases
in the wage gap reduce violence against women, consistent with a household
bargaining model. These findings shed new light on the health production
process as well as observed income gradients in health and suggest that in
addition to addressing concerns of equity and efficiency, pay parity can also
improve the health of American women via reductions in violence.
Poverty, Violence and
Health: The Impact of Domestic Violence During Pregnancy on Newborn Health Journal of Human
Resources
(2011), 46(3): 518-538.
Two percent of women in the US suffer from intimate partner violence annually, with poor and minority women disproportionately affected. I provide evidence of an important negative externality associated with domestic violence by estimating a negative and causal relationship between violence during pregnancy and newborn health, exploiting variation in the enforcement of laws against domestic violence for identification. I find that hospitalization for an assault while pregnant reduces birth weight by 163 grams. This sheds new light on the infant health production process as well as observed income gradients in health given that poor mothers are disproportionately affected by violence.
Love,
Hate and Murder: Commitment Devices in Violent Relationships (with Pedro Dal Bo) Journal of
Public Economics, 2009.
Many
violent relationships are characterized by a high degree of cyclicality: women
who are the victims of domestic violence often leave and return multiple times.
To explain this we develop a model of time inconsistent preferences in the
context of domestic violence. This time inconsistency generates a demand for
commitment. We present supporting evidence that women in violent relationships
display time inconsistent preferences by examining their demand for commitment
devices. We find that no-drop policies – which compel the prosecutor to
continue with prosecution even if the victim expresses a desire to drop the
charges – result in an increase in reporting. No-drop policies also result in a
decrease in the number of men murdered by intimates suggesting that some women in
violent relationships move away from an extreme type of commitment device when
a less costly one is offered.
Neighborhood
Violence and Urban Youth in The Problems of Disadvantaged Youth: An Economic Perspective,
Jonathon Gruber, editor, 2009.
Three quarters of American children have been exposed to neighborhood violence in their lifetimes. Most of the existing research has concluded that exposure to violence leads to restricted emotional development, aggressive behavior and poor school outcomes. However, this literature fails to account for the fact that children exposed to neighborhood violence are highly disadvantaged in other ways: they are more likely to be black, poor and have poorly educated parents. As such, it is not clear whether exposure to violence or the underlying measures of disadvantage are responsible for the poor child outcomes observed. Using individual survey data on urban youth and their families from Los Angeles, we find that the most violent neighborhoods are also characterized by the highest degree of disadvantage: greatest poverty, highest unemployment, least education. And while living in a violent neighborhood increases the probability of exposure to violence, within violent neighborhoods those personally exposed to street violence are significantly more disadvantaged and are more likely to associate with violent peers than their unexposed neighbors. Once we control for observed and unobserved family disadvantage, the impact of violence declines for some child outcomes, suggesting that underlying disadvantage explains some of the negative outcomes observed, but not all - it is still the case that associating with violent peers is negatively correlated with cognitive test scores. In addition, when we control for underlying differences across families, the relationship between violence and internalizing behavioral problems appears stronger.
Public
Health Insurance, Program Take-up and Child Health,
Review of Economics and Statistics, August 2007.
Of
the ten million uninsured children in 1996, nearly half were eligible for
public health insurance (Medicaid) but not enrolled. In response, policy
efforts to reduce the uninsured have shifted from expanding Medicaid
eligibility to increasing take-up among those eligible. However, little is
known about the reasons poor families fail to enroll or consequences. Using a
unique data set I find that information and administrative costs are important
barriers to enrollment, especially for Hispanics and Asians. In addition,
enrolling children in Medicaid before get sick promotes the use of preventative
care, reduces the need for hospitalization, and improves health.
Does Managed Care Hurt Health? Evidence
from Medicaid Mothers (with Janet Currie
and Enrico Moretti) Review of Economics and
Statistics, August 2007.
Most
Americans are now in some form of managed care plan that restricts access to
services in order to reduce costs. It is difficult to determine whether these
restrictions affect health because individuals and firms self-select into
managed care. We investigate the effect of managed care using a California law
that required some pregnant women on Medicaid to enter managed care.We use a unique longitudinal database of California
births in which we observe changes in the regime faced by individual mothers
between births. We find that Medicaid managed care reduced the quality of
prenatal care and increased low birth weight, prematurity, and neonatal death.
The
Impact of Child Support on Fertility, Parental Investments and Child Well-being
(with Sara McLanahan)
Journal of
Human Resources, Winter
2006.
Increasing
the probability of paying child support, in addition to increasing resources
available for investment in children, also may alter the incentives faced by
men to have children out of wedlock. We find that strengthening child support
enforcement leads men to have fewer out-of-wedlock births and among those who
do become fathers, to do so with more educated women and those with a higher
propensity to invest in children. Thus, policies that compel men to pay child
support may affect child outcomes through two pathways: an increase in
financial resources and a birth selection process.
Access
to Care, Provider Choice and the Infant Health Gradient
(with Adriana Lleras-Muney
and Mark Stabile) American Economic Review Papers and
Proceedings, May
2005.
This paper explores whether choice of provider explains any of the observed infant health gradients, and if so, why poor women choose different providers than their richer neighbors. We exploit an exogenous change in policy that occurred in California in the early 1990s that suddenly increased Medicaid payments to hospitals and which lead to a sharp change in where women with Medicaid delivered. To characterize the extent to which poor women responded to the increase in provider access, we calculate hospital segregation indices (which measure the extent to which Medicaid mothers delivered in separate hospitals than privately insured mothers residing in the same geographic area) both before and after the policy change for each market in California and show that it fell sharply after the policy change. Even though black mothers responded least to the increase in provider choice afforded by the policy change, they benefited the most from hospital desegregation in terms of reduced neonatal mortality and decreased incidence of very low birth weight. In contrast, other groups with lower initial neonatal mortality moved more and gained less in terms of improvements in birth outcomes.
Home
Alone: Supervision After School and Child Behavior, Journal
of Public Economics, 2004.
As
female participation in the labor force continues to grow in the US, so too
does reliance on non-parental child care. However, the high cost of child care
has impeded the ability of many working mothers to find sufficient child care
for their children. As a result, as recently as 1998 over eight million
children ages five to 14 spent time without adult supervision on a regular
basis in the US. I examine the effect of the lack of adult supervision after
school on a panel of school-age children using ordinary least squares and fixed
effect estimation. I find that children with adult supervision are less likely to
skip school, use alcohol or marijuana, steal something or hurt someone. These
findings suggest that expanding after school or child care programs typically
geared to preschool-age children to accommodate more school-age children may
have important consequences for their human capital development and labor
market outcomes later in life.
Networks or Neighborhoods? Interpreting Correlations in the
Use of Publicly-Funded Maternity Care in California
(with Janet Currie) Journal of Public Economics,
2004.
This
study focuses on ‘‘network effects’’ in the utilization of publicly-funded
prenatal care using Vital Statistics data from California for 1989–2000.
Networks are defined using 5-digit zip codes and a woman’s racial or ethnic
group. Like others, we find evidence that the use of public programs is highly
correlated within groups defined using race/ethnicity
and neighborhoods. These correlations persist even when we control for many
unobserved characteristics by including zip code-year fixed effects, and when
we focus on the interaction between own group behavior and measures of the
potential for contacts with other members of the group (‘‘contact
availability’’). However, the richness of our data allows us to go further and
to conduct several tests of one important hypothesis about networks: that the
estimated effects represent information sharing within groups. The results cast
doubt on the idea that the observed correlations can be interpreted as evidence
of information sharing. In particular, we find estimated effects to be as large
or larger among women who have previously used the program as among first-time
users
Low
Take-up in Medicaid: Does Outreach Matter and For Whom? American
Economic Review Papers and Proceedings, May 2003.
Work
in Progress
Juvenile
Incarceration & Adult Outcomes: Evidence from Randomly-Assigned Judges (with Joe Doyle)
Over
100,000 youths are currently incarcerated in the US, yet little is known
whether such a penalty deters future crime or interrupts human capital
formation in a way that increases the likelihood of later criminal behavior.
This paper uses the incarceration tendency of randomly assigned judges as an
instrumental variable to estimate causal effects of juvenile incarceration on
adult recidivism. Using nearly 140,000 juvenile offenders in Cook County,
Illinois, we find that those incarcerated as juveniles are 2.5 times more
likely to be incarcerated as an adult—a correlation that likely overstates the
effect of juvenile incarceration due to endogeneity
concerns. Our instrumental variable estimates are smaller, though still large:
a 70% increase in the likelihood of adult incarceration for juveniles on the
margin of incarceration. Marginal treatment effect estimates show that these
results are found across a relatively wide range of judges, which adds
confidence that our estimates are uncontaminated by selection into juvenile
detention.