We test for an effect of Arizona's 2007 Legal Arizona Workers Act (LAWA) on the proportion of the state's population characterized as noncitizen Hispanic. We use the synthetic control method to select a group of states against which Arizona's population trends can be compared. We document a notable and statistically significant reduction in the proportion of the Hispanic noncitizen population in Arizona. The decline observed matches the timing of LAWA's implementation, deviates from the time series for the synthetic control group, and stands out relative to the distribution of placebo estimates for other states in the nation.

Employers became more willing to hire a range of disadvantaged workers during the 1990s boom—including minorities, workers with certain stigmas (such as welfare recipients), and those without recent experience or high school diplomas. The wages paid to newly hired less-skilled workers also increased. On the other hand, employers' demand for specific skill certification rose over time, as did their use of certain screens. The results suggest that the tight labor markets of the late 1990s, in conjunction with other secular changes, raised hiring costs and induced employers to shift toward screens that seemed more cost-effective.

We present quasi-experimental estimates of the effect of changes in workers' compensation benefits on benefit duration and application frequency, using administrative data for California. Our design exploits two increases in temporary disability benefits occurring during the mid-1990s. We find consistent increases in the duration among injured workers whose benefits were affected by the schedule changes, and some evidence indicating that the likelihood of filing for benefits conditional on being injured is responsive to benefit levels. Finally, we evaluate whether the frequency effect on applying for indemnity benefits introduces a sample selection bias into standard quasi-experimental estimates of duration benefit elasticities.

We use a sample of tenth-graders to test for peer-group influences on the propensity to engage in five activities: drug use, alcohol drinking, cigarette smoking, church going, and the likelihood of dropping out of high school. We find strong evidence of peer-group effects at the school level for all activities. Tests for bias due to endogenous school choice yield mixed results. We find evidence of endogeneity bias for two of the five activities analyzed (drug use and alcohol drinking). On the whole, these results confirm the findings of previous research concerning interaction effects at the neighborhood level.

It is generally believed that the increased incidence of homelessness in the United States has arisen from broad societal factors, such as changes in the institutionalization of the mentally ill, increases in drug addiction and alcohol usage, and so forth. This paper presents a comprehensive test of the alternate hypothesis that variations in homelessness arise from changed circumstances in the housing market and in the income distribution. We assemble essentially all the systematic information available on homelessness in U.S. urban areas: census counts, shelter bed counts, records of transfer payments, and administrative agency estimates. We estimate similar statistical models using four different samples of data on the incidence of homelessness, defined according to very different criteria. Our results suggest that simple economic principles governing the availability and pricing of housing and the growth in demand for the lowest-quality housing explain a large portion of the variation in homelessness among U.S. metropolitan housing markets. Furthermore, rather modest improvements in the affordability of rental housing or its availability can substantially reduce the incidence of homelessness in the United States.