Quantifying Intrinsic and Extrinsic Contributions to Human Longevity: Application of a Two-Process Vitality Model to the Human Mortality Database

The rise in human life expectancy has involved declines in intrinsic and extrinsic mortality processes associated, respectively, with senescence and environmental challenges. To better understand the factors driving this rise, we apply a two-process vitality model to data from the Human Mortality Database. Model parameters yield intrinsic and extrinsic cumulative survival curves from which we derive intrinsic and extrinsic expected life spans (ELS). Intrinsic ELS, a measure of longevity acted on by intrinsic, physiological factors, changed slowly over two centuries and then entered a second phase of increasing longevity ostensibly brought on by improvements in old-age death reduction technologies and cumulative health behaviors throughout life. The model partitions the majority of the increase in life expectancy before 1950 to increasing extrinsic ELS driven by reductions in environmental, event-based health challenges in both childhood and adulthood. In the post-1950 era, the extrinsic ELS of females appears to be converging to the intrinsic ELS, whereas the extrinsic ELS of males is approximately 20 years lower than the intrinsic ELS.     

Impact of low fertility and early age at sterilisation on women’s formal education and skill development in South India

This paper examines the impact of low fertility and early age at sterilisation on women’s formal education and skill development in South India. Multilevel ordered-logit modelling of pseudo-cohort data re-organised from the three rounds of National Family Health Survey, and thematic analysis of qualitative data collected from Tamil Nadu and Kerala states showed no evidence of women’s resumption of formal education or uptake of skill development training in the post-sterilisation and post-childcare period. While resuming formal education in the post-sterilisation and post-childcare period is harder to achieve for various individual, household, community and policy reasons, there is greater preparedness and support for women to undertake skill development training. As low fertility and early age at sterilisation are widely regarded as the emerging reproductive norm in India, post-sterilisation and -childcare women will be a significant population group both in number and in proportional terms. No government policies or programs have so far recognised this group. India’s new government should consider targeted skill development programs for post-sterilisation and -childcare women appropriate to their social, economic and educational levels. An important contribution of the family planning program, particularly female sterilisation, for the economic and social development of the family and the wider society will otherwise be lost.     

Welfare reform and immigrant fertility

Immigration policy is at the forefront of US policy discussions, and the use of welfare benefits by immigrants has been hotly debated. In 1996, Congress enacted welfare reform legislation, which imposed strict restrictions on welfare eligibility for noncitizens. However, a number of states restored access to welfare benefits to immigrants that had been cut out in the federal welfare reform law. Using data from the Current Population Survey, we examine whether immigrant women adjusted their childbearing in response to changes in the generosity of welfare benefits at the state-level. We find that noncitizen women reduced their fertility in response to cutbacks imposed by the legislation. Our findings, which prove robust to a number of identification and robustness checks, underscore how immigrants respond to state-level policies and provide insight into the potential impacts of comprehensive immigration reform, particularly the components related to the path to citizenship and access to public benefits.     

The Emergence of Two Distinct Fertility Regimes in Economically Advanced Countries

Beginning in 2000, in economically advanced countries, a remarkable bifurcation in fertility levels has emerged, with one group in the moderate range of period total fertility rates, about 1.9, and the other at 1.3. The upper branch consists of countries in Northern and Western Europe, Oceania and the United States; the lower branch includes Central, Southern, and Eastern Europe, and East and Southeast Asia. A review of the major theories for low-fertility countries reveals that none of them would have predicted this specific bifurcation. We argue that those countries with fertility levels close to replacement level have institutional arrangements, and related policies, that make it easier, not easy, for women to combine the worker and mother roles. The institutional details are quite different across countries, suggesting that multiple combinations of institutional arrangements and policies can lead to the same country-level fertility outcome. Canada, the only exception to this bifurcation, illustrates the importance of the different institutional structures in Québec compared to the rest of Canada.     

Comparing the U.S. Decennial Census Coverage Estimates for Children from Demographic Analysis and Coverage Measurement Surveys

Following every U.S. decennial census since 1960, the U.S. Census Bureau has evaluated the completeness of coverage using two different methods. Demographic analysis (DA) compares the census counts to a set of independent population estimates to infer coverage differences by age, sex, and race. The survey-based approach (also called dual system estimation or DSE) provides coverage estimates based on matching data from a post-enumeration survey to census records. This paper reviews the fundamentals of the two methodological approaches and then initially examines the results of these two methods for the 2010 decennial census in terms of consistency and inconsistency for age groups. The authors find that the two methods produce relatively consistent results for all age groups, except for young children. Consequently, the paper focuses on the results for children. Results of the 1990, 2000, and 2010 decennial censuses are shown for the overall population in this age group and by demographic detail (age, race, and Hispanic origin). Among children, the DA and DSE results are most inconsistent for the population aged 0–4 and most consistent for ages 10–17. Results also show that DA and DSE are more consistent for Black than non-Black populations. The authors discuss possible explanations for the differences in the two methods for young children and conclude that the DSE approach may underestimate the net undercount of young children due to correlation bias.     

Climate,migration, and the local food security context: introducing Terra Populus

Studies investigating the connection between environmental factors and migration are difficult to execute because they require the integration of microdata and spatial information. In this article, we introduce the novel, publically available data extraction system Terra Populus (TerraPop), which was designed to facilitate population–environment studies. We showcase the use of TerraPop by exploring variations in the climate–migration association in Burkina Faso and Senegal based on differences in the local food security context. Food security was approximated using anthropometric indicators of child stunting and wasting derived from Demographic and Health Surveys and linked to the TerraPop extract of climate and migration information. We find that an increase in heat waves was associated with a decrease in international migration from Burkina Faso, while excessive precipitation increased international moves from Senegal. Significant interactions reveal that the adverse effects of heat waves and droughts are strongly amplified in highly food insecure Senegalese departments.     

Family Structure and Children’s Economic Well-Being: Incorporating Same-Sex Cohabiting Mother Families

Research on family structure and child well-being rarely includes children in same-sex parent families, a notable omission since 28 % of female–female couple households contain children. Using the 2010–2013 pooled current population survey (CPS), we examined children’s economic well-being by family structure. These data were ideal for this study because they included a sizeable number of children in same-sex cohabiting mother families and the CPS measured both official and supplemental poverty, incorporating the cohabiting partner. Using the official poverty measure, children in same-sex cohabiting mother families were more likely to be poor than their counterparts in either different-sex cohabiting or married parent families. Using the supplemental poverty measure, children in same-sex mother families were no more likely to be poor than children in all other types of different-sex two-parent families.