Seminar Series

Aging is an evolutionarily labile trait that is likely shaped by a diversity of sources of natural selection. Two such mechanisms are sexual selection, or selection caused by competition among members of one sex for reproductive access to members of the other, and kin selection, which can be thought of selection arising from associations between fitness and social interactions. While various models have been used to argue for (or against) their importance in the evolution of aging, strategies for direct measurements of these selective forces are lacking.

Douglas Almond's use of the 1918 U.S. influenza pandemic as a natural experiment led to the seminal works on the subject of in utero health's impact on later life outcomes. The identification strength and clarity of his work, though, is driven by the inherent natural experiment supposition of random assignment. By using data from the 1920 and 1930 U.S. census, this study investigates this keystone assumption and shows that the families of the "treatment" cohort used by Douglas Almond were significantly less literate and economically prosperous than the families of the "control" group.

The results of recent evaluations of genome wide association (GWA) studies of complex phenotypic traits, including age at disease onset or life span, showed that such traits are typically affected by a large number of "small-effect-low-significance" alleles, which were excluded from further analyses in traditional GWA studies. In this talk we show that the joint influence of such genetic variants on human life span can be substantial and highly statistically significant.

Populations across the globe are experiencing demographic transitions related to aging, migration and women joining the paid labor force. In spite of these major demographic transitions, work places policies and practices have not often been responsive to such demographic changes, especially in the United States. Health may be impacted by the mounting demands experienced by many workers, especially among women in low wage occupations. Findings related to these demographic transitions are presented. In addition, recent findings from a study of low wage employees are discussed.

Sampling from a network using a random walk based approach such as Respondent Driven Sampling (RDS) is difficult because the sample can get stuck in isolated clusters of the network, reducing precision. In this paper we propose an alternative strategy Network Sampling with Memory (NSM) that uses social network data collected from respondents to increase the efficiency of the sampling process.

Executive functions are a suite of related cognitive functions that allow one to hold in mind goal relevant information and exclude from mind goal irrelevant information. Based on clinical and neuroimaging studies cognitive neuroscientists believe that these functions are central to the performance of goal directed behavior.

Extant estimates of the number of deaths that resulted from the Khmer-Rouge ruling of Cambodia range from half a million to over three million excess deaths--a huge range considering that the country's total population size was about 8 million at the outset of the Khmer-Rouge regime. In this presentation, I describe this unsatisfactory range and investigate whether it can be narrowed with either new data or a better approach.

Political and economic transition is often blamed for Russia's 40% surge in deaths between 1990 and 1994 (the "Russian Mortality Crisis"). Highlighting that increases in mortality occurred primarily among alcohol-related causes and among working-age men (the heaviest drinkers), this paper investigates a different explanation: the demise of the 1985-1988 Gorbachev Anti-Alcohol Campaign.

There is growing evidence that local conditions, particularly economic considerations, shape the geographic dispersion of immigrant groups. Yet our understanding of the impact of local variation in public policies on immigrants internal settlement patterns remains rudimentary. This paper takes advantage of local area variation in immigration policies and economic conditions to estimate their unique impact on changes in the size of local Mexican immigrant populations between 2007 and 2009.

In 1950 men and women in the United States had a combined life expectancy of 68.9 years, the 12th highest life expectancy at birth in the world. Today, life expectancy is up to 79.2 years, yet the country is now 28th on the list, behind the United Kingdom, Korea, Canada, and France, among others. This presentation examines patterns in international differences in life expectancy above age 50 and assesses the evidence and arguments that have been advanced to explain the poor position of the United States relative to other countries.