The War at Home: Effects of Vietnam-Era Military Service on Post-War Household Stability

Prior researchers have deployed the Vietnam-era draft lottery as an instrument to estimate causal effects of military service on health and income. This research has shown that effects of veteran status on mortality and earnings that appeared shortly after the war seem to have dissipated by 2000. While these are important outcomes to economists, by focusing on them, researchers may be neglecting an area of life that could be more sensitive to the psychological effects of military service: household and family life. In the present study we use the same IV approach to model the causal impact of Vietnam- era military service on four novel outcomes: residential stability, marital stability, housing tenure and extended family living arrangements. In analysis of the 2000 U.S. Census and the 2005 American Community Survey, we find that veteran status has no effect on housing tenure or residential stability. However, in the ACS sample, being a veteran appears to lower the likelihood of marital disruption, and results for extended family living arrangements appear to change signs across the two samples. Meanwhile, results tend to be strongest for whites.

Parental Educational Investment and Children's Academic Risk: Estimates of the Impact of Sibship Size and Birth Order from Exogenous Variations in Fertility

The stylized fact that individuals who come from families with more children are disadvantaged in the schooling process has been one of the most robust effects in human capital and stratification research over the last few decades. For example, Featherman and Hauser (1978: 242-243) estimate that each additional brother or sister costs respondents on the order of a fifth of a year of schooling. However, more recent analyses suggest that the detrimental effects of sibship size on children's educational achievement might be spurious. We extend these recent analyses of spuriousness versus causality using a different method and a different set of outcome measures. We suggest an instrumental variable approach to estimate the effect of sibship size on children's private school attendance and on their likelihood of being held back in school. Specifically, we deploy the sex-mix instrument used by Angrist and Evans (1998). Analyses of educational data from the 1990 PUMS five percent sample reveal that children from larger families are less likely to attend private school and are more likely to be held back in school. Our estimates are smaller than traditional OLS estimates, but are nevertheless greater than zero. Most interesting is the fact that the effect of sibship size is uniformly strongest for latter-born children and zero for first born children.

Malaria ecology, child mortality & fertility.

The broad determinants of fertility are thought to be reasonably well identified by demographers, though the detailed quantitative drivers of fertility levels and changes are less well understood. This paper uses a novel ecological index of malaria transmission to study the effect of child mortality on fertility. We find that temporal variation in the ecology of the disease is well-correlated to mortality, and pernicious malaria conditions lead to higher fertility rates. We then argue that most of this effect occurs through child mortality, and estimate the effect of child mortality changes on fertility. Our findings add to the literature on disease and fertility, and contribute to the suggestive evidence that child mortality reductions have a causal effect on fertility changes

Modeling Gene‐Environment Interactions With Quasi‐Natural Experiments

This overview develops new empirical models that can effectively document Gene × Environment (G×E) interactions in observational data. Current G×E studies are often unable to support causal inference because they use endogenous measures of the environment or fail to adequately address the nonrandom distribution of genes across environments, confounding estimates. Comprehensive measures of genetic variation are incorporated into quasi‐natural experimental designs to exploit exogenous environmental shocks or isolate variation in environmental exposure to avoid potential confounders. In addition, we offer insights from population genetics that improve upon extant approaches to address problems from population stratification. Together, these tools offer a powerful way forward for G×E research on the origin and development of social inequality across the life course.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/136008/1/jopy12227_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/136008/2/jopy12227.pd

The Effect of Daughters on Partisanship and Social Attitudes Toward Woman

This is the peer reviewed version of the following article: Conley, D. and Rauscher, E. (2013), The Effect of Daughters on Partisanship and Social Attitudes Toward Women. Sociol Forum, 28: 700–718. doi:10.1111/socf.12055, which has been published in final form at http://doi.org/10.1111/socf.12055. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Washington (2008) finds that daughters promote liberal voting (at least with respect to women's issues) among U.S. Congress members and attributes this finding to socialization. However, daughters’ influence could manifest differently for elite politicians and the general citizenry either due to self-selection or the Trivers-Willard hypothesis, which suggests that parents invest differently in male and female children depending on their social status. Using nationally representative data from the General Social Survey, this study asks whether biological daughters affect political party identification, traditional views of women, or opinions about abortion and teen sex. We find that female offspring promote identification with the more conservative Republican Party, but this effect depends on social status. There is no evidence that daughters promote liberal views of women and less consistent evidence that they influence views of abortion or teen sex. Overall, evidence supports the Trivers-Willard hypothesis, but with a more complex interaction by social status

Genetic Interactions with Prenatal Social Environment: Effects on Academic and Behavioral Outcomes

Numerous studies report gene-environment interactions, suggesting that specific alleles have different effects on social outcomes depending on environment. In all these studies, however, environmental conditions are potentially endogenous to unmeasured genetic characteristics. That is, it could be that the observed interaction effects actually reflect underlying genetic tendencies that lead individuals into certain environments. What is critical to move this literature forward is random environmental variation that we know is not correlated with innate characteristics of subjects. We exploit a natural experiment that randomizes a particular stressor—birth weight discordance within twin pairs—to address this challenge and ask: Do random differences in early environment (prenatal nutrition) moderate genetic effects on depression, delinquency, or GPA? Using Add Health data, the only consistently significant allele–birth weight interaction we reveal works in the opposite direction of Caspi et al.’s classic finding regarding the interaction of maltreatment with genetic variation in the serotonin transporter promoter. Less robust interactions found for DRD2 and MAOA are consistent with this pattern that reverses prior findings. These results do not necessarily overturn existing research but support our methodological point that gene-environment research must address endogeneity

Africa's Lagging Demographic Transition: Evidence from Exogenous Impacts of Malaria Ecology and Agricultural Technology

Much of Africa has not yet gone through a "demographic transition" to reduced mortality and fertility rates. The fact that the continent's countries remain mired in a Malthusian crisis of high mortality, high fertility, and rapid population growth (with an accompanying state of chronic extreme poverty) has been attributed to many factors ranging from the status of women, pro-natalist policies, poverty itself, and social institutions. There remains, however, a large degree of uncertainty among demographers as to the relative importance of these factors on a comparative or historical basis. Moreover, econometric estimation is complicated by endogeneity among fertility and other variables of interest. We attempt to improve estimation (particularly of the effect of the child mortality variable) by deploying exogenous variation in the ecology of malaria transmission and in agricultural productivity through the staggered introduction of Green Revolution, high-yield seed varieties. Results show that child mortality (proxied by infant mortality) is by far the most important factor among those explaining aggregate total fertility rates, followed by farm productivity. Female literacy (or schooling) and aggregate income do not seem to matter as much, comparatively.

The Equal Environments Assumption in the Post-Genomic Age: Using Misclassified Twins to Estimate Bias in Heritability Models

While it has long been known that genetic-environmental covariance is likely to be non-trivial and confound estimates of narrow-sense (additive) heritability for social and behavioral outcomes, there has not been an effective way to address this concern. Indeed, in a classic paper, Goldberger (1979) shows that by varying assumptions of the GE-covariance, a researcher can drive the estimated heritability of an outcome, such as IQ, down to zero or up close to one. Survey questions that attempt to measure directly the extent to which more genetically similar kin (such as monozygotic twins) also share more similar environmental conditions than, say, dizygotic twins, represent poor attempts to gauge a very complex underlying phenomenon of GE-covariance. Methods that rely on concordance between interviewer classification and self-report offer similar concerns about validity. In the present study, we take advantage of a natural experiment to address this issue from another angle: Misclassification of twin zygosity in a nationally-representative study (Add Health). Since such twins were reared under one “environmental regime of similarity” while genetically belonging to another group, this reverses the typical GE-covariance and allows us bounded estimates of heritability for a range of outcomes of interest to medical and behavioral scientists.

The Long-Term Effects of Military Conscription on Mortality: Estimates from the Vietnam-era Draft Lottery

Research on the effects of Vietnam military service suggests that Vietnam veterans experienced significantly higher mortality than both non-Vietnam veterans and the civilian population at large. These results, however, may be biased by non-random selection into the military if unobserved background differences between veterans and non-veterans affect mortality directly. The present study generates unbiased estimates of the causal impact of Vietnam era draft eligibility on male mortality. Using records from the Vietnam draft lottery to assign decedents born 1950-1952 draft lottery numbers, the study estimates excess mortality among observed draft eligible male decedents as compared to the (1) expected proportion of draft eligible decedents given Vietnam draft eligibility cutoffs and (2) observed proportion of draft eligible female decedents. The results demonstrate that there appears to be no effect of draft exposure on mortality (even cause-specific death rates). When we examine population subgroups—including splits by race, educational attainment, nativity and marital status—we find weak evidence for an interaction between education and draft eligibility. On the whole, these results suggest that previous research, which has shown that Vietnam-era veterans experienced significantly higher mortality than non-veterans, may be biased by non-random selection into the military and may thus overstate the need for compensatory government pensions.

Health Shocks, Insurance Status and Net Worth: Intra- and Inter-Generational Effects

An extensive literature has documented a robust correlation between socioeconomic status—measured in a variety of ways—and health outcomes; however, much uncertainty remains regarding what causal processes underlie this association. The present paper builds on a growing literature that seeks to better document how and why wealth and SES are related. Specifically, we ask the extent to which health shocks affect net worth—a less-studied dimension of socioeconomic status. Given a lack of instruments that meet the exclusion restriction, we use data from the Panel Study of Income Dynamics to pursue a first-differences identification strategy. We estimate a parameter for acute illnesses (which should have a causal effect on wave-to-wave wealth changes) and compare this coefficient to a counterfactual parameter for the presence of chronic illnesses (which we argue should be less causally related to wealth differences year-to-year). Additionally, we interact these health indicators with insurance status as a further test that the health-wealth relationship is likely causal net of covariates. Results show that the onset of an acute illness has a negative effect on family wealth levels and that the onset of chronic illnesses only makes an impact when it occurs for those uninsured. In intergenerational models, parental health insurance status also seems to matter. When parents suffer from chronic illness and have no health insurance, adult children’s net worth declines. Adult children in white families also face a greater likelihood of falling into debt (excluding wealth from home equity) when parental medical expenses increase. Together, these findings suggest that health dynamics play an important role in intergenerational stratification processes—at least under the current health regime of the United States.