Over the 1980s, there were sharp increases in the return to schooling estimated with conventional wage regressions. The authors explore whether the relationship between ability and schooling changed over this period in ways that would have increased the schooling coefficient in these regressions. Their empirical results reject the hypothesis that an increase in the bias of the schooling coefficient, due to a change in the relationship between ability and schooling, has contributed to observed increases in the return to schooling. The authors also find that the increase in the schooling return has occurred for workers with relatively high levels of academic ability.

We examine evidence on omitted-ability bias in estimates of the economic return to schooling, using proxies for unobserved ability. We consider measurement error in these ability proxies and the potential endogeneity of both experience and schooling, and examine wages at labor market entry and later. Including ability proxies reduces the estimate of the return to schooling, and instrumenting for these proxies reduces the estimated return still further. Instrumenting for schooling leads to considerably higher estimates of the return to schooling, although only for wages at labor market entry. This estimated return generally reverts to being near (although still above) the OLS estimate if we allow experience to be endogenous. In contrast, for observations at least a few years after labor market entry, the evidence indicates that OLS estimates of the return to schooling that ignore omitted ability are, if anything, biased upward rather than downward.

Using cross-state variation in minimum wages, we observe a positive relationship between the minimum wage and the number of alcohol-related accidents involving teen drivers. A similar effect is not observed when examining accidents among adults. The results are consistent with a positive income elasticity for alcoholic beverages and driving activities among young people, in particular for consumption out of discretionary income accorded by higher minimum wages. Evidence of a sizable impact of beer taxes on alcohol-related accidents among youths suggests that beer taxes are one avenue for policymakers to consider in counteracting this unintended consequence of minimum wages.