Published Papers

Rising student loan debt and concerns over unaffordable payments provide rationale for "income-driven repayment" (IDR) plans, which aim to protect borrowers from default and resulting financial consequences by linking payments to income. We estimate the causal effect of IDR payment burdens on loan repayment and attainment for several cohorts of first-time IDR applicants using a regression discontinuity design. Borrowers who are not required to make payments see short-run reductions in delinquency and default risk, primarily due to lower costs of inattention, but these effects fade over the longer run as some borrowers become disconnected from the student loan repayment system.

We document changes in the rate at which borrowers repay their student loans by calculating a borrower-level loan paydown rate — the percentage change in outstanding debt relative to debt at repayment entry. The typical borrower entering repayment in 2005 repaid 26 percent of their loan within five years versus 5 percent for the typical borrower entering repayment in 2014. Paydown rate declines vary by educational attainment, school type, outstanding debt at repayment entry, and repayment plan. Shifts in repayment plan and debt can explain some of the shift in the distribution of paydown rates over time, but most remains unexplained.

We describe the empirical relationship between local government boundaries and residential segregation in the United States. First, we study recent changes in the distribution of segregation within and between local governments in all metropolitan areas, using census block data on residential demographics over the period 1990–2020. We find that segregation across local government boundaries explains a substantial share of racial stratification, which has changed only little over the last thirty years. Next, we use spatial regression discontinuity methods to distinguish between household sorting due to neighborhood amenities and public goods provided by local governments. The prevalence of demographic discontinuities at local government boundaries suggest that between-jurisdiction segregation patterns cannot be explained solely by proximity to neighborhood amenities. We discuss implications for policy, showing that both between-jurisdiction segregation and jurisdictional discontinuities can partly explain the correlation between total segregation and racial gaps in educational outcomes.

School segregation is determined both by residential sorting and local policies, such as the drawing of attendance boundaries and school siting. This paper develops an approach to understanding the relative importance of these factors by calculating the distance-minimizing assignment of students to schools and assessing whether actual assignments differ systematically by race. Using census data and attendance boundary maps for nearly 1,600 school districts, I find that attendance boundaries create 5 percent more integration than a distance-minimizing baseline, while school siting plays almost no role. Residential segregation alone explains more than 100 percent of school segregation in the United States.

We examine the impact of the expansion of charter schools on racial segregation in public schools, defined using multiple measures of racial sorting and isolation. Our research design utilizes between-grade differences in charter expansion within school systems and an instrumental variables approach leveraging charter school openings. Charter schools modestly increase school segregation for Black, Hispanic, Asian, and White students. On average, charters have caused a 6 percent decrease in the relative likelihood of Black and Hispanic students being exposed to schoolmates of other racial or ethnic groups. For metropolitan areas, our analysis reveals countervailing forces, as charters reduce segregation between districts.