The Wages of Sinistrality: Handedness, Brain Structure and Human Capital Accumulation

Left- and right-handed individuals have different brain structures, particularly in relation to language processing. Using five data sets from the US and UK, I show that poor infant health increases the likelihood of a child being left-handed. I argue that handedness can thus be used to explore the long-run impacts of differential brain structure generated in part by poor infant health. Even conditional on infant health and family background, lefties exhibit economically and statistically significant human capital deficits relative to righties. Compared to righties, lefties score a tenth of a standard deviation lower on measures of cognitive skill and, contrary to popular wisdom, are not over-represented at the high end of the distribution. Lefties have more emotional and behavioral problems, have more learning disabilities such as dyslexia, complete less schooling, and work in less cognitively intensive occupations. Differences between left- and right-handed siblings are similar in magnitude. Most strikingly, lefties have six percent lower annual earnings than righties, a gap that can largely be explained by these differences in cognitive skill, disabilities, schooling and occupational choice. Lefties work in more manually intensive occupations than do righties, further suggesting that lefties’ primary labor market disadvantage is cognitive rather than physical. Those likely be left-handed due to genetics show smaller or no deficits relative to righties, suggesting the importance of environmental shocks as the source of disadvantage. Handedness provides parents and schools a costlessly observable characteristic with which to identify young children whose cognitive and behavioral development may warrant additional attention

Gold Standards?: State Standards Reform and Student Achievement

Proponents of the recent and widely adopted Common Core State Standards argue that high quality curricular standards are critical to students’ educational success. Little clear evidence exists, however, linking the quality of such standards to student achievement. I remedy this by connecting data on state-level student achievement from 1994-2011 with measures of the quality of states’ curricular standards as judged by two independent organizations at three different moments in time. I show that, within states, changes in the quality of standards have little impact on overall student achievement. Improved standards do, however, raise achievement of 8th graders in low-scoring states, particularly for low-scoring students. Given the known weaknesses of U.S. middle schools, this result suggests that standards may be beneficial in settings where pedagogy would otherwise be poor

First Degree Earns: The Impact of College Quality on College Completion Rates

We use a Massachusetts merit aid program to provide the first clear causal evidence on the impact of college quality on students’ postsecondary enrollment decisions and rates of degree completion, where college quality is defined by a variety of measures including on-time graduation rates. High school students with test scores above multiple thresholds were granted tuition waivers at in-state public colleges of lower quality than the average alternative available to such students. A binding score regression discontinuity design comparing students just above and below these thresholds yields two main findings. First, students are remarkably willing to forego college quality for relatively small amounts of money. Second, choosing a lower quality college significantly lowers on-time completion rates, a result driven by highskilled students who would otherwise have attended higher quality colleges. For the marginal student, enrolling at an in-state public college lowered the probability of graduating on time by more than 40%. The low completion rates of scholarship users imply the program had little impact on the in-state production of college degrees. More broadly, these results suggest that the critically important task of improving college quality requires steps beyond merely changing the composition of the student body

Bankruptcy Law and The Cost of Credit: The Impact of Cramdown on Mortgage Interest Rates

The role of bankruptcy law in credit markets has received renewed attention in the aftermath of the housing bubble collapse. The fundamental challenge for research on this topic is to separate the impact of legal factors from other features of the credit environment. We do so by exploiting historical variation in federal judicial rulings regarding whether Chapter 13 bankruptcy filers could reduce the principal owed on a home loan to the home’s market value. The practice, known as cramdown, was definitively prohibited by the Supreme Court in 1993. We find evidence that home loans closed during the time when cramdown was allowed had interest rates 10-20 basis points higher than loans closed in the same state when cramdown was not allowed, which translates to a roughly 1-2 percent increase in monthly payments. Consistent with the theory that lenders are pricing in the risk of principal modification, interest rate increases are higher for the riskiest borrowers and zero for the least risky, as well as higher in states where Chapter 13 filing is more common. Though the price of credit rises slightly, we find no evidence of a change in the quantity of credit provided. The relatively small impacts of cramdown on the cost of credit suggests that the insurance benefits of bankruptcy may be relatively inexpensive

The Labor of Division: Returns to Compulsory Math Coursework

Labor economists know that a year of schooling raises earnings but have little evidence on the impact of specific courses completed. I identify the impact of math coursework on earnings using the differential timing of state-level increases in high school graduation requirements as a source of exogenous variation. The increased requirements induced large increases in both the completed math coursework and earnings of blacks, particularly black males. Two-sample instrumental variable estimates suggest that each additional year of math raised blacks' earnings by 5-9%, accounting for a large fraction of the value of a year of schooling. Closer analysis suggests that much of this effect comes from black students who attend non-white schools and who will not attend college. The earnings impact of additional math coursework is robust to changes in empirical specification, is not driven by selection into the labor force, and persists when earnings are conditioned on educational attainment. The reforms close one fifth of the earnings gap between black and white males. Estimates for whites are similar to those of blacks but are much noisier due to the reforms' weaker impact on white students' coursework. These results suggest that math coursework is an important determinant of the labor market return to schooling, that simple minimum requirements largely benefit low-skilled students, and that more demanding requirements might be necessary to improve the outcomes of high-skilled students

Intensive Math Instruction and Educational Attainment

We study an intensive math instruction policy that assigned low-skilled 9th graders to an algebra course that doubled instructional time, altered peer composition and emphasized problem solving skills. A regression discontinuity design shows substantial positive impacts of double-dose algebra on credits earned, test scores, high school graduation and college enrollment rates. Test score effects under-predict attainment effects, highlighting the importance of long-run evaluation of such a policy. Perhaps because the intervention focused on verbal exposition of mathematical concepts, the impact was largest for students with below average reading skills, emphasizing the need to target interventions toward appropriately skilled students

Middle School Math Acceleration and Equitable Access to 8th Grade Algebra: Evidence from the Wake County Public School System

School districts across the country have struggled to increase the proportion of students taking algebra by 8th grade, thought to be an important milestone on the pathway to college preparedness. We highlight key features of a research collaboration between the Wake County Public School System and Harvard University that have enabled investigation of one such effort to solve this problem. In 2010, the district began assigning middle school students to accelerated math coursework leading to 8th grade algebra on the basis of a clearly defined measured of prior academic skill. We document two important facts. First, use of this new rule greatly reduced the relationship between course assignment and student factors such as income and race while increasing the relationship between course assignment and academic skill. Second, using a regression discontinuity analytic strategy, we show that the assignment rule had strong impacts on the fraction of students on track to complete algebra by 8th grade. Students placed in accelerated math were exposed to higher-skilled peers but larger class sizes. We describe future plans for assessing impacts on achievement and high school course-taking outcomes.Other Research Uni

The relationship between siblings’ college choices: Evidence from one million SAT-taking families

Research consistently shows that college choice in an important predictor of college completion and labor market outcomes. These longer term implications of college choice, combined with suboptimal choices made by many low-income but high-achieving students, has sparked several large-scale initiatives to improve college choice. Strategically targeting those students most susceptible to making questionable decisions in the college-choice process remains challenging, as variation in college choice is largely unexplained by easily measurable socio-demographic characteristics. This paper explores the potential to improve upon existing models and, more generally, to better understand college choice by documenting the similarities in college enrollment patterns between younger and older siblings. To do so, we identify siblings in the millions of SAT test-takers between the 2004 and 2011 high school graduation cohorts. We find that younger siblings enroll in the same college as their older sibling 21.2 percent of the time. Also, conditional on their own SAT scores, we find that younger siblings whose older siblings enrolled in four-year colleges and the most selective colleges are 17.4 and 21.3 percentage points, respectively, more likely to themselves enroll in four-year and the most selective colleges. Overall, adding characteristics and enrollment decisions of older siblings to standard college choice models improves model fit and consequently, are valuable pieces of information for explanatory and predictive power.Economic

Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin