|
James Feyrer, Dartmouth College
and NBER; Dimitra Politi, Brown University;
and David N. Weil, Brown University
and NBER
The Economic Effects of Micronutrient
Deficiency: Evidence from Salt Iodization in the United States.
Iodine deficiency is the leading cause of preventable mental retardation
in the world today. Iodine deficiency was common in the developed world
until the introduction of iodized salt in the 1920s. The incidence of
iodine deficiency is connected to low iodine levels in the soil and water. Feyrer,
Politi, and Weil examine the impact of salt iodization in the
United States United States by taking advantage of this natural geographic
variation. Areas with high pre-treatment levels of iodine deficiency provide
a treatment group that they can compare to a control group of low iodine
deficiency areas. In the United States,
salt was iodized over a very short period of time around 1924. We use
previously unused data collected during WWI and WWII to compare outcomes of
cohorts born before and after iodization, in localities that were naturally
poor and rich in iodine. We find evidence of the beneficial effects of
iodization on the cognitive abilities of the cohorts exposed to it.
Karen Norberg, Washington University and NBER; Richard Grucza,
Washington University, St. Louis; and Laura Bierut, Washington University,
St. Louis
Adolescence as a Sensitive Period:
Long-term Effects of Minimum Purchase Age Laws on Alcohol and Drug Use
Disorders
Many studies have found that early drinking initiation predicts higher
risk of later alcohol and substance use problems, but it is not known
whether policies influencing the age of onset of regular drinking would
affect later drinking and substance use patterns, or whether early drinking
onset is simply a marker for existing vulnerability to alcohol and
substance use disorders. Norberg, Grucza, and Bierut
use a "natural experiment" study design to compare the prevalence
of DSM-IV alcohol and substance use disorders among adult subjects exposed
to different minimum legal purchase age laws (MLPAs) in the 1970s and
1980s. The sample includes 33,869 respondents born in the United
States from 1948-1970, drawn from two
nationally representative cross-sectional surveys: the 1991 National
Longitudinal Alcohol Epidemiological Survey (NLAES) and the 2001 National
Epidemiological Study of Alcohol and Related Conditions (NESARC). Analyses
control for gender, race, parental alcohol problems, age at assessment, and
state and year fixed effects; some analyses also condition on age at
drinking initiation, educational attainment, age at first marriage and age
at first birth. The authors find that individuals who were legally allowed
to purchase alcohol before age 21 had more than 25 percent greater odds of
a current alcohol-use disorder or substance-use disorder (that is,alcohol
or illegal drug use problems), with no apparent decline in effects with
age. Purchase-age effects were similar among males and females, blacks and
others, persons who did or did not report having parents with alcohol
problems, and respondents reporting onset of drinking before and after age
16. The authors conclude that exposure to a lower minimum legal purchase
age is associated with significantly higher risk of a current alcohol or
other substance use disorder in middle adulthood. These findings are
consistent with the hypothesis that late adolescence may be a
"sensitive period" for environmental influences on the formation
of alcohol use patterns.
Grant Miller, Stanford University and NBER; Diana M. Pinto, Pontificia
Universidad ; and Marcos Vera-Hernandez, University College London
Supply- vs. Demand-Side Rationing
in Developing Country Health Insurance: Evidence from Colombia's 'Regimen
Subsidiado'
In developing countries, medical costs associated with unexpected
illness are an important source of economic risk confronting households.
Health insurance expansions therefore are a public policy priority, but
they also produce socially undesirable consumer incentives for wasteful
medical care use. Miller, Pinto, and Vera-Hernandez
study the first major developing country effort (Colombia's
Regimen Subsidiado) to promote efficient consumption under health insurance
without sacrificing risk protection. Using a regression discontinuity
approach, they find that by improving supply-side incentives through
high-powered health insurance contracting, Colombia has provided risk
protection with minimal wasteful consumption - and it has also increased
the use of services with positive externalities (with some small associated
health gains).
|
Martha J. Bailey, University
of Michigan and NBER; and
Nzinga Broussard, Claremont McKenna
College
The Impact of Federal Family Planning Grants under the War on Poverty
Over 40 years ago, the U.S.
government embraced a policy of funding domestic family planning services.
The effects of these programs have been controversial since their
inception. Bailey and Broussard generate event-study
estimates of the impact of federal family planning grants by relying on
variation in the timing of awards. Their results provide new evidence that
federal family planning grants had a large and statistically-significant
impact on birth rates up to 15 years after the date of award. There is no
evidence of significant reductions in maternal or neonatal mortality or the
incidence of low birth weight.
Price V. Fishback, University of Arizona and NBER; and Melissa A.
Thomasson, Miami University and NBER
The Effects of Experiencing the Great
Depression as a Child on Socioeconomic and Health Outcomes
Fishback and Thomasson use twentieth century data to
examine how macroeconomic conditions just before and after birth affect
infants when they become adults. Their analysis focuses on the worst
downturn ever experienced in the United
States — the Great Depression --
although they do not restrict their analysis to the Depression period.
Merging data reported by respondents in decadal U.S. Census microdata from 1970-80
with information on the path of state per capita income during the
individual's childhood years in the state of birth, the authors find that
individuals born in poorer states (and in states with lower rates of income
growth after their birth) are more likely to be high school dropouts, earn
lower incomes, and have greater rates of disability than individuals born
in states with higher incomes, even after controlling for socioeconomic
characteristics such as race and education, year of birth, state of birth,
and state of current residence. These results suggest that fluctuations in
state-wide economic activity during the infant and early childhood period
may have long-term consequences for an individual's socioeconomic status
and health outcomes.
John Brown, Clark University
Fertility Control with Imperfect Methods: Strategies of
Family Building and the Choice of Technique during the German Fertility
Transition, 1885-1915
An extensive body of literature, mostly drawn from the Princeton
project on the European fertility transition, is based on the critical
assertion that fertility control during the transition was
parity-dependent. The indirect evidence for this proposition is flawed.
Following up on an argument formulated by Santow (1995) and David and
Sanderson (1986), Brown revisits the question of control during the
transition by placing it within the framework of dynamic models of
fertility under uncertainty. He examines the choice of technique and the
strategy for family building during the period of the transition in Germany,
1885 to 1915. Available technologies varied in efficiency, cost, and
disutility, posing significant tradeoffs for couples. After establishing
the relative efficiency of most of the technologies available to couples,
Brown examines the decision to use birth control and the choice of birth
control strategy. His econometric analysis uses a detailed survey of
fertility outcomes, birth control practices, and social and economic
information that includes much of the period of the transition. His results
suggest that the logic of birth control technologies and desired family
size created a bifurcated distribution of strategy choices.
Daron Acemoglu, MIT and NBER; David Autor, MIT and NBER; and Amanda
Pallais, MIT,
Assessing the Rising Return to Education and Ability: Evidence from Army
Veterans
A large literature has focused on rising inequality both between and
within groups since the late 1970s. The increasing inequality between
educational groups is typically considered to reflect an increase in the
return to skill. Yet, little is known about what this skill represents,
whether it is an increasing return to formal schooling or to cognitive
ability. Acemoglu, Autor, and Pallais exploit a new
dataset on Army veterans to investigate the changes in the returns to
education and (normally) unobserved ability over time. Their dataset,
created by combining Social Security earnings data with Army records,
contains education data, AFQT scores, and 20 years of Social Security
earnings data for more than 1.5 million Army veterans born between 1942 and
1964. The researchers show that the observed return to education increased
between 1978 and 2005, controlling for AFQT scores, and the return to AFQT
scores increased, controlling for education. They then write down a
stylized single-index model in which the mapping between skill markers
(such as education and AFQT) is time-invariant, while the relationship
between skill and log earnings shifts linearly over time. While they reject
the most restrictive cardinal implications of this model, an ordinal
version of it provides a surprisingly good fit. Additionally, their initial
results suggest that different levels of educational attainment represent
separate, imperfectly substitutable skills, whereas they cannot reject that
the skills represented by different levels of cognitive ability are
perfectly substitutable.
|