Anna Aizer - Research
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.
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.
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.