Enrico Moretti

Mother's Education and the Intergenerational Transmission of Human Capital: Evidence from College Openings

We examine the effect of maternal education on birth outcomes using Vital Statistics Natality data for 1970 to 1999. We also assess the importance of four channels through which maternal education may improve birth outcomes: use of prenatal care, smoking, marriage, and fertility. In an effort to account for the endogeneity of educational attainment, we use data about the availability of colleges in the womans county in her seventeenth year as an instrument for maternal education. We find that higher maternal education improves infant health, as measured by birth weight and gestational age. It also increases the probability that a new mother is married, reduces parity, increases use of prenatal care, and reduces smoking, suggesting that these may be important pathways for the ultimate effect on health. Our results add to the growing body of literature which suggests that estimates of the returns to education which focus only on increases in wages understate the total return.

Workers’ Education, Spillovers, and Productivity: Evidence from Plant-Level Production Functions

I assess the magnitude of human capital spillovers by estimating production functions using a unique firm-worker matched data set. Productivity of plants in cities that experience large increases in the share of college graduates rises more than the productivity of similar plants in cities that experience small increases in the share of college graduates. These productivity gains are offset by increased labor costs. Using three alternative measures of economic distance-input-output flows, technological specialization, and patent citations-I find that within a city, spillovers between industries that are economically close are larger than spillovers between industries that are economically distant.

Biology as Destiny? Short and Long-Run Determinants of Intergenerational Transmission of Birth Weight

We use a unique data set of California births to ask whether intergenerational correlations in health contribute to the perpetuation of economic status. We find that if a mother was low birth weight, her child is significantly more likely to be low birth weight, even when we compare mothers who are sisters. Second, the intergenerational transmission of low birth weight is stronger for mothers in high poverty zip codes. Third, low birth weight affects proxies for later socioeconomic status. Fourth, these effects are stronger for women born in high poverty zip codes.

Why do Most Italian Youths Live with Their Parents? Intergenerational Transfers and Household Structure

More than 80% of Italian men aged 18-30 live with their parents. We argue that one contributing factor to this remarkably high rate of cohabitation is parents’ tastes for co-residence. In order to investigate the role of parental preferences, we estimate the effect of exogenous changes in parental income on rates of cohabitation in Italy using SHIW micro-data from 1989 to 2000. The key econometric issue is the potential endogeneity of parental income. In order to identify a source of exogenous variation in parental income, we use changes in fathers’ retirement age induced by the 1992 reform of the Italian Social Security system as an instrumental variable for parental income. By raising retirement age, this reform forced some fathers to remain in the labour market longer than they would have otherwise, therefore raising their disposable income. We use a two-sample instrumental variable (TSIV) strategy. Our TSIV estimates indicate that a rise in parents’ income significantly raises the children’s propensity to live at home: a 10% increase in annual parental income results in approximately a 10% rise in the proportion of boys living with their parents. Although we cannot definitely rule out alternative interpretations, these results are consistent with our hypothesis that cohabitation is a normal good for Italian parents.

Extreme Weather Events, Mortality and Migration

We estimate the effect of extreme weather on life expectancy in the United States. Using high-frequency data, we find that both extreme heat and cold result in immediate increases in mortality. The increase in mortality following extreme heat appears mostly driven by near-term displacement, while the increase in mortality following extreme cold is long lasting. We estimate that the number of annual deaths attributable to cold temperature is 0.8 of average annual deaths in our sample. The longevity gains associated with mobility from the Northeast to the Southwest account for 4 to 7 of the total gains in life expectancy experienced by the U.S. population over the past thirty years.

The Dynamics of Criminal Behavior: Evidence from Weather Shocks

While the persistence of criminal activity is well documented, this may be due to persistence in the unobserved determinants of crime. There are good reasons to believe, however, that there may actually be a negative relationship between crime rates in a particular area due to temporal displacement. We exploit the correlation between weather and crime to examine the short-run dynamics of crime. Using variation in lagged crime rates due to weather shocks, we find that the positive serial correlation is reversed. These findings suggest that the long-run impact of temporary crime-prevention efforts may be smaller than the short-run effects.

Do microfinance programs help families insure consumption against illness

Families in developing countries face enormous financial risks from major illness both in terms of the cost of medical care and the loss in income associated with reduced labor supply and productivity. We test whether access to microfinancial savings and lending institutions helps Indonesian families smooth consumption after declines in adult health. In general, results support the importance of these institutions in helping families to self-insure consumption against health shocks.

The Effect of Fast Food Restaurants on Obesity and Weight Gain

We investigate how changes in the supply of fast food restaurants affect weight outcomes of 3 million children and 3 million pregnant women. Among ninth graders, a fast food restaurant within 0.1 miles of a school results in a 5.2 percent increase in obesity rates. Among pregnant women, a fast-food restaurant within 0.5 miles of residence results in a 1.6 percent increase in the probability of gaining over 20 kilos. The implied effects on caloric intake are one order of magnitude larger for children than for mothers, consistent with smaller travel cost for adults. Non-fast food restaurants and future fast-food restaurants are uncorrelated with weight outcomes. (JEL I12, J13, J16, L83)

Pollution, Health, and Avoidance Behavior: Evidence from the Ports of Los Angeles

A pervasive problem in estimating the costs of pollution is that optimizing individuals may compensate for increases in pollution by reducing their exposure, resulting in estimates that understate the full welfare costs. To account for this issue, measurement error, and environmental confounding, we estimate the health effects of ozone using daily boat traffic at the port of Los Angeles as an instrumental variable for ozone. We estimate that ozone causes at least

DOES MANAGED CARE HURT HEALTH? EVIDENCE FROM MEDICAID MOTHERS

44 million in annual costs in Los Angeles from respiratory related hospitalizations alone and that the cost of avoidance behavior is at least