We develop a decentralized Bayesian model of college admissions with two ranked colleges, heterogeneous students, and two realistic match frictions: students find it costly to apply to college, and college evaluations of their applications are uncertain. Students thus face a portfolio choice problem in their application decision, while colleges choose admissions standards that act like market-clearing prices. Enrollment at each college is affected by the standards at the other college through student portfolio reallocation. In equilibrium, student-college sorting may fail: weaker students sometimes apply more aggressively, and the weaker college might impose higher standards. Applying our framework, we analyse affirmative action, showing how it induces minority applicants to construct their application portfolios as if they were majority students of higher caliber.

Deadlines and late penalties are widely used to incentivize effort. Tighter deadlines and higher penalties induce higher effort, but increase the agent's risk. We model how these contract terms affect the work rate and time-to-completion in a procurement setting, characterizing the efficient contract design. Using new micro-level data on Minnesota highway construction contracts that includes day-by-day information on work plans, hours worked and delays, we find evidence of ex post moral hazard: contractors adjust their effort level during the course of the contract in response to unanticipated productivity shocks, in a way that is consistent with our theoretical predictions. We next build an econometric model that endogenizes the completion time as a function of the contract terms and the productivity shocks, and simulate how commuter welfare and contractor costs vary across different terms and shocks. Accounting for the traffic delays caused by construction, switching to a more efficient contract design would increase welfare by 22.5% of the contract value while increasing the standard deviation of contractor costs—a measure of risk—by less than 1% of the contract value.

In the late 1930s, the National Association for the Advancement of Colored People (NAACP) launched a campaign to equalize Black and white teacher salaries in the de jure segregated schools of the American South. We estimate the effect of teacher pay on educational attainment exploiting variation in Black salary gains over time across Southern counties with different Black enrollment shares and across states by whether subsequent policy reinforced or resisted court rulings favorable to the NAACP. Using newly collected county panel data, we find that Black teacher salary gains contributed to the large reductions in racial inequality in school enrollment and grade progression in the South at midcentury.

An important class of active labor market policy has received little impact evaluation: immigration barriers intended to raise wages and employment by shrinking labor supply. Theories of endogenous technical advance raise the possibility of limited or even perverse impact. We study a natural policy experiment: the exclusion of almost half a million Mexican bracero farm workers from the United States to improve farm labor market conditions. With novel labor market data we measure state-level exposure to exclusion, and model the absent changes in technology or crop mix. We fail to reject zero labor market impact, inconsistent with this model. (JEL J15, J18, J22, J31, J43, J61, O33)