NBER Publications by William T. Harbaugh

We report results from economic experiments that provide a direct test of the hypothesis that criminal behavior responds rationally to changes in the possible rewards and in the probability and severity of punishment. The experiments involve decisions that are best described as petty larceny, and are done using high school and college students who can anonymously take real money from each other. We find that decisions about whether and how much to steal are, in general, rational and responsive to the variations in tradeoffs, and sometimes, though not always, to the overall availability of criminal opportunities.

This paper uses an updated and revised panel data set on ambient air pollution in cities world-wide to examine the robustness of the evidence for the existence of an inverted U-shaped relationship between national income and pollution. We test the sensitivity of the pollution-income relationship to functional forms, to additional covariates, and to changes in the nations, cities, and years sampled. We find that the results are highly sensitive to these changes. We conclude that there is little empirical support for an inverted-U-shaped relationship between several important air pollutants and national income in these data.