Knowledge that Transforms

We conduct an experiment in which subjects face the same questions repeated multiple times, with repetitions of two types: (1) following the literature, the repetitions are distant from each other; (2) in a novel treatment, the repetitions are in a row, and subjects are told that the questions will be repeated. We find that a large majority of subjects exhibit stochastic choice in both cases. We discuss the implications for models of stochastic choice.

What are the consequences of international trade on the skill premium? We incorporate skill-intensity differences across firms and sectors into a standard model of international trade. Reductions in trade costs reallocate factors toward a country's comparative advantage sectors, increasing the skill premium in countries with a comparative advantage in skill-intensive sectors and decreasing it elsewhere. Reductions in trade costs also reallocate factors toward more productive and skill-intensive firms within sectors and toward skill-intensive sectors in all countries, increasing the skill premium in all countries. Quantitatively, we find that trade liberalization increases the skill premium in almost all countries.

Minority and disadvantaged students are typically underrepresented in selective programs that use merit-based admission. Urban school districts may set different referral and admission thresholds based on income and race (affirmative action), and they may exploit differences in achievement relative to ability across race and income groups (profiling). We develop and estimate a model that provides a unified treatment of affirmative action and profiling. We find profiling by race and income and affirmative action for low-income students. Counterfactual analysis reveals that these policies achieve more than 80 percent of African American enrollment that could be attained by race-based affirmative action.

I provide new evidence on the relative “powers” of contraception and abortion policy in effecting the dramatic social transformations of the 1960s and 1970s. Trends in sexual behavior suggest that young women’s increased access to the birth control pill fueled the sexual revolution, but neither these trends nor difference-in-difference estimates support the view that this also led to substantial changes in family formation. Rather, the estimates robustly suggest that it was liberalized access to abortion that allowed large numbers of women to delay marriage and motherhood.

We study competition in matching markets with random heterogeneous preferences and an unequal number of agents on either side. First, we show that even the slightest imbalance yields an essentially unique stable matching. Second, we give a tight description of stable outcomes, showing that matching markets are extremely competitive. Each agent on the short side of the market is matched with one of his top choices, and each agent on the long side either is unmatched or does almost no better than being matched with a random partner. Our results suggest that any matching market is likely to have a small core, explaining why small cores are empirically ubiquitous.

How does political unrest influence public policy? We assume that protests are an emotional reaction to unfair treatment. Individuals have a consistent view of fairness that internalizes government constraints. Individuals accept lower welfare if the government is more constrained. This resignation effect induces a benevolent government to delay unpleasant choices and accumulate public debt to mitigate social unrest. More radical and homogeneous groups are more prone to unrest and hence more influential. Even if the government is benevolent and all groups are identical in their propensity to riot, equilibrium policy can be distorted. The evidence is consistent with these implications.