Genetic and environmental influences on cognition during childhood

The basic methodology of behavior genetics is described in the context of the twin and sibling/adoption design. Results of applying this model to cross-sectional data on cognitive development throughout the lifespan are presented. Results from a large longitudinal twin and adoption study of general intelligence are presented to illustrate the use of the basic behavior genetic model in studying the causes of continuity and change in development. A special model is presented for the study of abnormal behavior occurring at the extremes of the distribution and an adaptation of the model is discussed for the study of genetic linkage or the mapping of quantitative trait loci (QTL). Results of applying this model to a sample of twins and kindred siblings indicated the presence of a major QTL for dyslexia on chromosome 6. The purpose of the paper is to illustrate the scope of behavior genetic methodology in studying individual differences in behavior in a biosocial context.     

Neighborhood selection and the social reproduction of concentrated racial inequality

In this paper, we consider neighborhood selection as a social process central to the reproduction of racial inequality in neighborhood attainment. We formulate a multilevel model that decomposes multiple sources of stability and change in longitudinal trajectories of achieved neighborhood income among nearly 4,000 Chicago families followed for up to seven years wherever they moved in the United States. Even after we adjust for a comprehensive set of fixed and time-varying covariates, racial inequality in neighborhood attainment is replicated by movers and stayers alike. We also study the emergent consequences of mobility pathways for neighborhood-level structure. The temporal sorting by individuals of different racial and ethnic groups combines to yield a structural pattern of flows between neighborhoods that generates virtually nonoverlapping income distributions and little exchange between minority and white areas. Selection and racially shaped hierarchies are thus mutually constituted and account for an apparent equilibrium of neighborhood inequality.     

Export agriculture is feeding malaria: a cross-national examination of the environmental and social causes of malaria prevalence

Malaria rates remain high across many less-developed regions, including Southeast Asia, Sub-Saharan Africa, and parts of Latin America. Although case studies find elevated malaria rates in locales with increased levels of environmental degradation, the current body of comparative environmental research lacks investigation of infectious disease trends. This study draws upon world-system theorizing to consider agricultural export flows and resulting alterations to the natural environment in poor nations as key causes of malaria prevalence. Additionally, relationships among world-system position, economic development, and socio-health characteristics are examined alongside the environmental predictors using structural equation modeling for data on 99 less-developed nations. The findings emphasize that deforestation and biodiversity loss associated with primary sector export flows are key drivers of malaria rates, alongside notable influences of basic health and social services. The results suggest that environmental and social conditions greatly shape malaria transmission in poor societies.     

The effects of maternal employment on child injuries and infectious disease

This article presents estimates of effects of maternal paid work and nonmaternal child care on injuries and infectious disease for children aged 12 to 36 months. Mother-child fixed-effects estimates are obtained by using data from the NICHD Study of Early Child Care. Estimates indicate that maternal employment itself has no statistically significant adverse effects on the incidence of infectious disease and injury. However greater time spent by children in center-based care is associated with increased rates of respiratory problems for children aged 12 to 36 months and increased rates of ear infections for children aged 12 to 24 months.     

Fertility, child care outside the home, and pay-as-you-go social security

We examine the long-run effects of the pay-as-you-go (PAYG) social security scheme on fertility and welfare of individuals in an overlapping generations model, assuming that child-care services are available in the market. We show that the impact of a tax increase on fertility depends on the relative magnitudes of the standard intergenerational redistribution effect through the social security system, the (implicit) subsidy effect through tax-exemption of child rearing at home, and the price effect through changes in the relative price of market child care, and that if parental child-rearing time is inelastic, a tax cut could bring about a Pareto-improving allocation.

Modeling urbanism: Economic,social and environmental stress in cities

The time has come for urban social indicator research to converge with the basic substantive efforts of urban researchers. Such a convergence may propel both basic and applied researchers toward more fruitful outcomes. This paper argues that the traditional model of urbanism provides the medium for the convergence. When urbanism is conceptualized to be multidimensional, seemingly discreet indicators of demographic, economic, social, and environmental conditions in cities may be incorporated into a more general model of urban structure and change. Specifically, using social indicators for 195 cities from ZPG's Children's Stress Index and the 1990 U.S. Census, we show empirically: (1) Urbanism is a complex factor with four distinct dimensions: demographic scale, economic stress, social stress, and environmental stress. (2) These four dimensions of urbanism may be reliably measured with standard composite variables used in today's social indicator research. (3) Within the Urbanism factor there are causal connections among the separate dimensions, the most basic of which is that asserted by arguments from the traditional theory of urbanism; specifically, that population size, density, and social heterogeneity are causally linked to stress in economic, social, and environmental systems of the city.     

The effects of social capital and social pressure on the intention to have a second or third child in France, Germany, and Bulgaria, 2004-05

This study investigates the importance of the effect of an individual's web of informal relationships with family and peers on the intention to have a second or third child. Drawing on sociological theories of social capital (help with childcare, emotional support) and social pressure, the study extends existing research by evaluating cross-national differences (between France, Germany, and Bulgaria) in the impact of personal network and institutional circumstances. It tests a non-linear relationship between social capital and fertility intentions. Social pressure and social capital are highly institutionally filtered, with the impact of personal network stronger where institutions are less family-supportive.     

Disease prevalence,disease incidence,and mortality in the United States and in England

We find that both disease incidence and disease prevalence are higher among Americans in age groups 55–64 and 70–80, indicating that Americans suffer from higher past cumulative disease risk and experience higher immediate risk of new disease onset compared with the English. In contrast, age-specific mortality rates are similar in the two countries, with an even higher risk among the English after age 65. We also examine reasons for the large financial gradients in mortality in the two countries. Among 55- to 64-year-olds, we estimate similar health gradients in income and wealth in both countries, but for 70- to 80-year-olds, we find no income gradient in the United Kingdom. Standard behavioral risk factor’s (work, marriage, obesity, exercise, and smoking) almost fully explain income gradients among those aged 55–64 in both countries and a significant part among Americans 70–80 years old. The most likely explanation of the absence of an English income gradient relates to the English income benefit system: below the median, retirement benefits are largely flat and independent of past income, and hence past health, during the working years. Finally, we report evidence using a long panel of American respondents that their subsequent mortality is not related to large changes in wealth experienced during the prior 10-year period.     

Differences between Hispanic and non-Hispanic families in social capital and child development: First-year findings from an experimental study

Disadvantages faced by Hispanic children in the U.S., compared to non-Hispanic Whites, have been widely reported. Economic differences account for some of the gaps, but the social isolation of Hispanic families also serves as a barrier to children's success. Whereas Hispanic families tend to have strong kinship networks, their social ties often do not encompass the school and other authority systems. As a result, Hispanic families may have less access to social capital, that is, relations of trust and shared expectations that foster the flow of relevant information and support social norms that contribute to children's academic and social development. To study the role of social capital in child development, we embarked on a school-randomized trial in two cities with large Hispanic populations: San Antonio, Texas, and Phoenix, Arizona. In this paper, we report on first-year data from what will be a three-year longitudinal study, including 24 of an eventual 52 schools and about 1300 of what will be a sample of over 3000 children. We aimed to manipulate social capital through an intervention called Families and Schools Together (FAST), a multi-family after-school program that enhances relations among families, between parents and schools, and between parents and children through a sequence of structured activities over 8 weekly sessions. In the first year, 12 schools were randomly assigned to participate in FAST, and 12 served as controls. Data come from district administrative records, surveys of parents prior to FAST, and surveys of parents and teachers immediately after FAST. Surveys prior to FAST confirm that Hispanic parents have less extensive parent–school networks compared to non-Hispanic Whites. Comparisons of school means on post-FAST surveys indicate that parents in FAST schools experience more extensive social networks than those in control schools, but the differences are much more apparent in Phoenix than in San Antonio. Similarly, a pattern of better behavioral outcomes for children in FAST schools is evident in Phoenix but not San Antonio. Individual-level comparisons suggest that for some outcomes, effects may be larger for non-Hispanic Whites than for Hispanics, which would undermine potential contributions to reducing inequality.     

Occupational influences on retirement,disability, and death

This research examines the alternative mechanisms by which occupations influence the nature and timing of older men's labor force withdrawal. We specifically assess the extent to which occupational factors operate directly and indirectly on exiting events and whether occupations constrain traditional determinants of labor force participation. Based on a discrete-time hazard modeling approach, the results substantiate that the occupational task activities--substantive complexity and physical demands--are key elements of the work environment that are evaluated against nonwork alternatives. In the case of retirement, these aspects of occupational attractiveness function as a dominant and direct force in retirement decision making. With regard to disability, the occupational attribute of substantive complexity operates as an indirect advantage (through higher wages) by reducing the risk of disability. Indicators of career continuity also influence retirement among older workers. Finally, the results suggest that financial characteristics and health problems are central to the distribution of older workers across the alternative destination statuses of retirement, disability, and death.     

The Effects of Childhood SNAP Use and Neighborhood Conditions on Adult Body Mass Index

The disproportionate number of individuals who are obese or overweight in the low-income U.S. population has raised interest in the influence of neighborhood conditions and public assistance programs on weight and health. Generally, neighborhood effects and program participation effects have been explored in separate studies. We unite these two areas of inquiry, using the 1968-2005 Panel Study of Income Dynamics (PSID) to examine the long-term effects of childhood Supplemental Nutrition Assistance Program (SNAP) participation, neighborhood conditions, and the interaction of these two, on adult body mass index (BMI). Using sibling fixed-effects models to account for selection bias, we find that relative to children in other low-income families, children in SNAP-recipient households have higher average adult BMI values. However, the effects of childhood SNAP usage are sensitive to both residential neighborhood and age at receipt. For those growing up in advantaged neighborhoods, projected adult BMI is higher for children in SNAP-recipient households than for children in low-income, nonrecipient households. In contrast, for those growing up in less-advantaged areas, adult BMI differences between children in SNAP-recipient and those in low-income, nonrecipient households are small. SNAP usage during preschool years (0 to 4) has no impact on adult BMI scores. However, at later childhood ages, the time elapsed receiving SNAP income increases adult BMI values relative to a condition of low-income nonreceipt.     

Living on the Edge: Neighborhood Boundaries and the Spatial Dynamics of Violent Crime

Neighborhood boundaries are a defining aspect of highly segregated urban areas. Yet, few studies examine the particular challenges and spatial processes that occur at the bordering region between two neighborhoods. Extending the growing literature on spatial interdependence, this article argues that neighborhood boundaries—defined as sharp changes in the racial or socioeconomic composition of neighborhoods—are a salient feature of the spatial structure with implications for violent crime and other outcomes. Boundaries lack the social control and cohesion of adjacent homogeneous areas, are contested between groups provoking intergroup conflict, and create opportunities for criminal behavior. This article presents evidence linking racial neighborhood boundaries to increased violent crime. The findings illustrate the importance of neighborhood boundaries for our understanding of spatial dimensions of population dynamics above and beyond the characteristics of neighborhoods.     

Individual and aggregate influences on the age at first birth

This study examines the role of both individual adolescent expectations of market and nonmarket income and aggregate influences on first birth timing for Blacks and Whites and for three birth cohorts of American women. Using two panels of the National Longitudinal surveys, results suggest that between-race differences in age at first birth result from differences in individual expectations about market and nonmarket income. Cohort differences in age at first birth result from relationship differences in both individual and aggregate influences, with aggregate influences differentially altering the role of individual expectations on first birth timing. These results suggest that employment policies that reduce poverty and increase wages would effectively delay childbearing. For Blacks, since early childbearing results from lower expectations about future economic success, similar fertility timing patterns between the races would result if Blacks had White employment and wage levels. Over time, these employment and wage policies will not only alter individual expectations about economic success but also will alter the impact of expectations on fertility timing.     

Neighborhood Social Disadvantage and Bicycling Behavior: A Big Data-Spatial Approach Based on Social Indicators

Social Indicators Research - Characterizing the travel behavior of disadvantaged neighborhoods is of significance for social inequality elimination and public well-being promotion. However, rather...     

Statistical and Perceived Diversity and Their Impacts on Neighborhood Social Cohesion in Germany,France and the Netherlands

The question whether ethnic diversity is associated with declining social cohesion has produced much controversy. We maintain that more attention must be paid to cognitive mechanisms to move the debate ahead. Using survey data from 938 localities in Germany, France, and the Netherlands, we explore a crucial individual-level mechanism: perceptions of diversity. We not only consider perceptions of the amount, but also of the qualitative nature of diversity. By asking about various qualitative aspects of diversity, we test the cognitive salience of three explanations that have been proposed in the literature for negative diversity effects: out-group biases, asymmetric preferences and coordination problems. We show that all three mechanisms matter. Perceptions both mediate statistical diversity effects, and have important explanatory power of their own. Moreover, we are able to address the question to what extend the relationship of perceived diversity and neighborhood social cohesion varies across policy contexts. Based on assumptions in the literature about positive impacts of inclusive and culturally pluralist immigrant integration policy approaches, we hypothesize that ethno-cultural diversity is less negatively related to neighborhood social cohesion in more inclusive policy contexts. Our results provide partial support for this hypothesis as perceived diversity has a significantly stronger negative impact on neighborhood cohesion in Germany.     

Changing chronic disease rates and longterm declines in functional limitation among older men

Functional limitation (difficulty walking, difficulty bending, paralysis, blindness in at least one eye, or deafness in at least one ear) in the United States fell at an average annual rate of 0.6% among men aged 50 to 74 from the early twentieth century to the early 1990s. Twenty-four percent of this decline is attributable to reductions in the debilitating effects of chronic conditions, 37% is attributable to reduced rates of chronic diseases, and the remainder is unexplained. The findings have implications for theories of the impact of declining mortality rates on the health of elderly people.     

Societal influences on body image dissatisfaction in younger and older women

Few studies have examined older women's body image. This study compared body image dissatisfaction (BID) and weight control practices; evaluated associations among BID, societal influences and concern for appropriateness (CFA); and identified the most important correlate of BID among younger (19-23) and older women (65-74). Questionnaires obtained information on demographics, weight control practices, societal influences (SATAQ-3), CFA and BID using the Figure Rating Scale. Findings revealed no difference in the prevalence of BID. The number of weight control practices and SATAQ-3 and CFA scores were correlated to BID. Pressure from the media was the most significant correlate of BID.     

Welfare states and social inequality: Key issues in contemporary cross-national research on social stratification and mobility

Research on welfare states and research on social stratification and mobility share a common concern for social inequality. Research on welfare states is usually comparatively designed, looking for similarities and variation across countries in a number of aspects related to social structure and social institutions. On the other hand, the basic model of social stratification, utilized in most cross-national research on social stratification and mobility, is an abstract model which does not specify why and how we are to understand cross-national differences. Yet for about 20 years or so, researchers within the social stratification community have undertaken several cross-national studies. This paper reviews a few selected studies within each area and summarizes their conclusions with regard to similarities versus differences between countries. In the final section of the paper, I discuss key issues for future work within cross-national research on social stratification.