Teacher Quality at the High-School Level: The Importance of Accounting for Tracks

Unlike in elementary school, high-school teacher effects may be confounded with both selection to tracks and unobserved track-level treatments. I document sizable confounding track effects, and show that traditional tests for the existence of teacher effects are likely biased. After accounting for these biases, high-school algebra and English teachers have much smaller test-score effects than found in previous studies. Moreover, unlike in elementary school, value-added estimates are weak predictors of teachers’ future performance. Results indicate that either (a) teachers are less influential in high school than in elementary school, or (b) test scores are a poor metric to measure teacher quality at the high-school level.

The Effects of an Incentive-Based High-School Intervention on College Outcomes

I analyze the effects of a program that pays both 11th and 12th grade students and teachers for passing scores on Advanced Placement exams on college outcomes. Using a difference-in-differences strategy, I find that affected students of all ethnicities attend college in greater numbers, have improved college GPAs, and are more likely to remain in college beyond their freshman year. Moreover, the program improves college outcomes even for those students who would have enrolled in college without the program. I also find evidence of increased college graduation for black and Hispanic students ─ suggesting that late high-school interventions may confer lasting positive effects on students, and may be effective at improving the educational outcomes of minority students. The finding of enduring benefits when extrinsic motivators are no longer provided is important in light of concerns that incentive-based-interventions may lead to undesirable practices such as “teaching-to-the-test” and cheating.

Can Higher-Achieving Peers Explain the Benefits to Attending Selective Schools?: Evidence from Trinidad and Tobago

Using exogenous secondary school assignments to remove self-selection bias to schools and peers within schools, I credibly estimate both (1) the effect of attending schools with higher-achieving peers, and (2) the direct effect of short-run peer quality improvements within schools, on the same population. While students at schools with higher-achieving peers have better academic achievement, within-school short-run increases in peer achievement improve outcomes only at high-achievement schools. Short-run (direct) peer quality accounts for only one tenth of school value-added on average, but at least one-third among the most selective schools. There are large and important differences by gender.

School Competition and Teacher Labor Markets: Evidence from Charter School Entry in North Carolina

I analyze changes in teacher turnover, hiring, effectiveness, and salaries at traditional public schools after the opening of a nearby charter school. While I find small effects on turnover overall, difficult to staff schools (low-income, high-minority share) hired fewer new teachers and experienced small declines in teacher quality. I also find evidence of a demand side response where schools increased teacher compensation to better retain quality teachers. The results are robust across a variety of alternate specifications to account for non-random charter entry.

Ability-grouping and Academic Inequality: Evidence From Rule-based Student Assignments

In Trinidad and Tobago students are assigned to secondary schools after fifth grade based on achievement tests, leading to large differences in the school environments to which students of differing initial levels of achievement are exposed. Using both a regression discontinuity design and rule-based instrumental variables to address self-selection bias, I find that being assigned to a school with higher-achieving peers has large positive effects on examination performance. These effects are about twice as large for girls than for boys. This suggests that ability-grouping reinforces achievement differences by assigning the weakest students to schools that provide the least value-added.

Do Social Connections Reduce Moral Hazard? Evidence from the New York City Taxi Industry

This study investigates the role of social networks in aligning the incentives of economic agents in settings with incomplete contracts. We study the New York City taxi industry where taxis are often leased and lessee-drivers have worse driving outcomes than owner-drivers as a result of a moral hazard associated with incomplete leasing contracts. Using instrumental variables and fixed-effects analyses, we find that: (1) drivers leasing from members of their country-of-birth community exhibit significantly reduced effects of moral hazard; (2) network effects appear to operate primarily via social sanctions; and (3) network benefits can help to explain the organization of the industry in terms of which drivers and owners form business relationships.

One for the Road: Public Transportation, Alcohol Consumption, and Intoxicated Driving

We exploit arguably exogenous train schedule changes in Washington DC to investigate the relationship between public transportation provision, the risky decision to consume alcohol, and the criminal decision to engage in alcohol–impaired driving. Using a triple differences strategy, we provide evidence that overall there was little effect on DUI arrests, alcohol related fatal traffic and alcohol related arrests. However, we find that these overall effects mask considerable heterogeneity across geographic areas and spatial shifting. Specifically, we find that areas close to bars that are within walking distance to Metro stations experience increases in alcohol related arrests and decreases in DUI arrests.