Better Schools, Less Crime?

I estimate the impact of attending a first-choice middle or high school on adult crime, using data from public school choice lotteries in Charlotte-Mecklenburg school district (CMS). Seven years after random assignment, lottery winners had been arrested for fewer serious crimes and had spent fewer days incarcerated. The gain in school quality as measured by peer and teacher inputs was equivalent to moving from one of the lowest-ranked schools to one at the district average. The reduction in crime comes largely from years after enrollment in the preferred school is complete. The impacts are concentrated among high-risk youth, who commit about 50% less crime across several different outcome measures and scalings of crime by severity. I find suggestive evidence that school quality explains more of the impact in high school, whereas peer effects are more important in middle school

Using School Choice Lotteries to Test Measures of School Effectiveness

Value-added models (VAMs) are increasingly used to measure school effectiveness. Yet random variation in school attendance is necessary to test the validity of VAMs, and to guide the selection of models for measuring causal effects of schools. In this paper, I use random assignment from a public school choice lottery to test the predictive power of VAM specifications. In VAMs with minimal controls and two or more years of prior data, I fail to reject the hypothesis that school effects are unbiased. Overall, many commonly used VAMs are accurate predictors of student achievement gains

Early Childhood Intervention and Life-Cycle Skill Development: Evidence from Head Start

This paper provides new evidence on the long-term benefits of Head Start using the National Longitudinal Survey of Youth. I compare siblings who differ in their participation in the program, controlling for a variety of pre-treatment covariates. I estimate that Head Start participants gain 0.23 standard deviations on a summary index of young adult outcomes. This closes one-third of the gap between children with median and bottom quartile family income, and is about 80 percent as large as model programs such as Perry Preschool. The long-term impact for disadvantaged children is large despite "fadeout" of test score gains

The For-Profit Postsecondary School Sector: Nimble Critters or Agile Predators?

Private for-profit institutions have been the fastest growing part of the U.S. higher education sector. For-profit enrollment increased from 0.2 percent to 9.1 percent of total enrollment in degree-granting schools from 1970 to 2009, and for-profit institutions account for the majority of enrollments in non-degree granting postsecondary schools. We describe the schools, students, and programs in the for-profit higher education sector, its phenomenal recent growth, and its relationship to the federal and state governments. Using the 2004 to 2009 Beginning Postsecondary Students (BPS) longitudinal survey we assess outcomes of a recent cohort of first-time undergraduates who attended for-profits relative to comparable students who attended community colleges or other public or private non-profit institutions. We find that relative to these other institutions, for-profits educate a larger fraction of minority, disadvantaged, and older students, and they have greater success at retaining students in their first year and getting them to complete short programs at the certificate and associate degree levels. But we also find that for-profit students end up with higher unemployment and “idleness” rates and lower earnings six years after entering programs than do comparable students from other schools, and that they have far greater student debt burdens and default rates on their student loans.

A Ground-Based Search for Thermal Emission from the Exoplanet TrES-1

Eclipsing planetary systems give us an important window on extrasolar planet atmospheres. By measuring the depth of the secondary eclipse, when the planet moves behind the star, we can estimate the strength of the thermal emission from the day side of the planet. Attaining a ground-based detection of one of these eclipses has proven to be a significant challenge, as time-dependent variations in instrument throughput and atmospheric seeing and absorption overwhelm the small signal of the eclipse at infrared wavelengths. We gathered a series of simultaneous L grism spectra of the transiting planet system TrES-1 and a nearby comparison star of comparable brightness, allowing us to correct for these effects in principle. Combining the data from two eclipses, we demonstrate a detection sensitivity of 0.15% in the eclipse depth relative to the stellar flux. This approaches the sensitivity required to detect the planetary emission, which theoretical models predict should lie between 0.05-0.1% of the stellar flux in our 2.9-4.3 micron bandpass. We explore the factors that ultimately limit the precision of this technique, and discuss potential avenues for future improvements.Comment: 10 pages, 1 table, four figures, accepted for publication in PAS

Into College, Out of Poverty? Policies to Increase the Postsecondary Attainment of the Poor

We review the experimental and quasi-experimental research evidence on the causal relationship between college costs and educational attainment, with a particular focus on low-income populations. The weight of the evidence indicates that reducing college costs can increase college entry and persistence. Simple and transparent programs appear to be most effective. Programs that link money to incentives and/or the takeup of academic support services appear to be particularly effective

The Lengthening of Childhood

Over the past 40 years, the age at which children enter first grade has slowly drifted upward. In the fall of 1968, 96 percent of six-year-old children were enrolled in first grade or above. By 2005, the proportion had dropped to 84 percent, mainly because a substantial share of six-year-olds were still in kindergarten. About a third of the increase in age at school entry can be explained by legal changes. Almost every state has increased the age at which children are allowed to start primary school. The other two-thirds of the increase in the age at school entry reflects the individual decisions of parents and teachers who choose to keep children out of kindergarten or first grade even when they are legally eligible to attend. This practice is sometimes called "red-shirting," a phrase originally used to describe the practice of holding college athletes out of play until they have grown larger and stronger. Red-shirting is referred to as "the gift of time" in education circles, reflecting a perception that children who have been allowed to mature for another year will benefit more from their schooling. As we will discuss, little evidence supports this perception. It is indeed true that in any grade, older children tend to perform better academically than the younger children. In the early grades there is a strong, positive relationship between a child's age in months and his performance relative to his peers. But there is little evidence that being older than your classmates has any long-term, positive effect on adult outcomes such as IQ, earnings, or educational attainment. By contrast, there is substantial evidence that entering school later reduces educational attainment (by increasing high school dropout rates) and depresses lifetime earnings (by delaying entry into the labor market)

Inversion of bottom-hole temperature data: the Pineview field, Utah-Wyoming thrust belt

Journal ArticleThe present day temperature field in a sedimentary basin is a constraint on the maturation of hydrocarbons; this temperature field may be estimated by inverting corrected bottom-hole temperature (BHT) data. Thirty-two BHTs from the Pineview oil field are corrected for drilling disturbances by a Horner plot and inverted for the geothermal gradient in nine formations