Cohort Studies Meeting

April 26, 2013
Dora Costa of the University of California, Los Angeles, Organizer

Douglas Almond, Columbia University and NBER; Hongbin Li, Tsing Hua University; and Shuang Zhang, Stanford University

Land Reform and Sex Selection in China

Following the death of Mao in 1976, land reform substantially increased rural incomes and heralded sweeping pro-market policies in China. Almond, Li, and Zhang consider whether the 1978-84 de-collectivization movement affected the tendency to sex select. Using variation in land reform timing from over 1,000 rural counties, they find that a second child who followed a daughter was 5.5 percent more likely to be a boy after land reform, thus doubling the underlying rate of sex selection in rural China. Better educated mothers were substantially more likely to respond to land reform by choosing a son. The One Child Policy was implemented over the same time period and is frequently blamed for increased sex selection during the early 1980s. The results of this study point to land reform as a more likely culprit.

Shelly Lundberg, University of California, Santa Barbara, and Robert Pollak, Washington University and NBER

The Uneven Retreat from Marriage in the U.S., 1950-2010

Lundberg and Pollak make two claims about marriage. First, they claim that intertemporal commitment is central to understanding marriage as an economic institution. Second, they claim that in early 21st century America, intertemporal commitment is valuable primarily because it facilitates investment in children. These claims are distinct, but together they imply that the desire to invest in children as a joint project has become a primary motive for marriage, and that differences in the expected returns to these investments explain the uneven retreat from marriage.

Gabriella Conti, University of Chicago and NBER

Early Life Adversity, Changes in Gene Expression, and Health: Evidence from Rhesus Monkeys

Conti exploits a unique ongoing experiment to analyze the effects of early rearing conditions on physical and mental health in a sample of rhesus monkeys. She analyzes the health records of 231 monkeys that were randomly allocated at birth across three rearing conditions: mother rearing, peer rearing, and surrogate peer rearing. She shows that the lack of a secure attachment relationship in the early years engendered by adverse rearing conditions has detrimental long-term effects on health that are not compensated for by a normal social environment later in life.

Prashant Bharadwaj, University of California, San Diego, and Petter Lundborg and Dan-Olof Rooth, Lund University

Fetal Origins in the Long Run

Although a large literature has examined the role of birth weight in determining short- and long-term outcomes, few papers have examined the relationship between birth weight and income at each point over the life cycle, and on outcomes in old age, such as mortality and early retirement. Bharadwaj, Lundborg,and Rooth provide evidence on the role of birth weight in determining these long-run outcomes using a twins fixed-effects methodology. A unique dataset on nearly all Swedish twins born between 1926-1958, containing information on birth weight, is linked with administrative records spanning a large fraction of life-time labor market participation and mortality. The author find that birth weight and adult mortality are only weakly connected. Birth weight and income are positively linked for large parts of the life cycle, and this is especially true of monozygotic male twins. They also find that lower birth-weight children are more likely to avail themselves of social assistance programs early in their life cycle. Finally, higher birth weight does not seem to affect take up of early retirement.

Carlos Villarreal, University of Chicago

Where the Other Half Lives: Evidence on the Origin and Persistence of Poor Neighborhoods from New York City 1830-2011

Villarreal documents the influence of early environmental conditions on the long-run distribution of housing prices and income on Manhattan Island. He reconstructs and links historical data in a spatial framework. An early topographic survey provides the location of historical marshes -- areas endowed with poor natural drainage -- which generated negative sanitation externalities at the time of settlement. Villarreal measures the influence of distance from those marshes on the rental price of housing from 1830 through 1940. He finds that an early aversion to historical marshes persists over time, despite the introduction of sanitation infrastructure and the discovery of communicable disease pathways. The persistence of that aversion to the initial environmental disamenity arises from the entrenchment of low-income individuals on historical marsh sites, while high-income individuals settle locations at ever increasing distances from the poor, helping to maintain the pattern of aversion to initial natural disamenities after the characteristics were no longer relevant.

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