Structural demand shifts and potential labor supply responses in the new century

It is widely recognized that inequality of labor market earnings in the United States grew dramatically in recent decades. Over the course of more than three decades, wage growth was weak to nonexistent at the bottom of the distribution, strong at the top of the distribution, and modest at the middle. While real hourly earnings of workers in the bottom 30 percent of the earnings distribution rose by no more than 10 percentage points, earnings of workers at the 90th percentile rose by more than 40 percentage points. What is much less widely known, however, is that this smooth, monotone growth of wage inequality is a feature of a specific time period--and that this time period has passed.Labor supply ; Wages

Explaining trends in wages, work, and occupations

The inequality of labor market earnings in the U.S. has increased dramatically in recent decades. However, closer examination of the data reveals two distinct periods of rising inequality: 1973–89 and 1989–2005. The first period was one of diverging wages throughout the distribution, while the second period was one of polarizing wage growth.Labor market ; Wages ; Employment

Why Do Temporary Help Firms Provide Free General Skills Training?

Nominally free, unrestricted training in portable computer skills is offered by the majority of U.S. temporary help supply (THS) establishments, a practice that is inconsistent with the competitive model of training. This paper asks why temporary help firms provide free general skills training. The answer proposed is that in addition to skills formation, training plays an informational role at THS firms by eliciting private information about worker ability. The model is built on the premise that training is more productive and therefore valuable to high ability workers. Firms offer a package of training and initially lower wages that induces self-selection. Workers of high perceived ability choose training in anticipation of a steeper wage profile while low ability workers are deterred by limited expected gains. Firms profit from their sunk training investment via their short-run informational advantage about ability and thereby limited monopsony power. Market competition among THS firms reduces employer rents, yielding higher wages and more training. Detailed tests of the model using representative establishment data on wages and training find strong support. The analysis demonstrates that beyond providing spot market labor, THS firms gather and sell information about worker quality to clients. The rapid growth of THS as a labor market information broker implies that the demand for worker screening is rising.

The Growth of Low Skill Service Jobs and the Polarization of the U.S. Labor Market

We offer an integrated explanation and empirical analysis of the polarization of U.S. employment and wages between 1980 and 2005, and the concurrent growth of low skill service occupations. We attribute polarization to the interaction between consumer preferences, which favor variety over specialization, and the falling cost of automating routine, codifiable job tasks. Applying a spatial equilibrium model, we derive, test, and confirm four implications of this hypothesis. Local labor markets that were specialized in routine activities differentially adopted information technology, reallocated low skill labor into service occupations (employment polarization), experienced earnings growth at the tails of the distribution (wage polarization), and received inflows of skilled labor.

Will Job Testing Harm Minority Workers?

Because minorities typically fare poorly on standardized tests, job testing is thought to pose an equity-efficiency trade-off: testing improves selection but reduces minority hiring. We develop a conceptual framework to assess when this tradeoff is likely to apply and evaluate the evidence for such a trade-off using data from a national retail firm whose 1,363 stores switched from informal to test-based worker screening over the course of on year. We document that testing yielded more productive hires at this firm -- raising median tenure by 10-plus percent. Consistent with prior research, minorities performed worse on the test. Yet, testing had no measurable impact on minority hiring, and productivity gains were uniformly large among minorities and non-minorities. These results suggest that job testing raised the precision of screening without introducing additional negative information about minority applicants, most plausibly because both the job test and the informal screen that preceded it were unbiased.

Do Temporary Help Jobs Improve Labor Market Outcomes for Low-Skilled Workers? Evidence from 'Work First'

A disproportionate share of low-skilled U.S. workers is employed by temporary-help firms. These firms offer rapid entry into paid employment, but temporary-help jobs are typically brief, and it is unknown whether they foster longer-term employment. We exploit a unique aspect of the city of Detroit’s welfare-to-work program, in which one in five jobs taken is obtained with a temporary-help firm, to identify the effects of temporary-help jobs on the subsequent labor market advancement of low-skilled workers. Welfare participants are assigned on a rotating basis to one of numerous program providers that have substantially different placement rates into temporary-help and regular (‘direct-hire’) jobs but offer otherwise standardized services. This gives rise to variation in job-taking rates that is functionally equivalent to random assignment. Using provider assignments as instrumental variables, we find that temporary-help job placements yield significant short-term earnings gains, but these gains are offset by lower earnings and less frequent employment over the next one to two years. Job placements with direct-hire employers, by contrast, substantially raise earnings over one, two, and three years following placement. The primary observable difference between these types of job placements is their effect on subsequent employment stability. Direct-hire placements roughly double the probability of ongoing employment in each of the first eight quarters following program assignment, while temporary help placements only positively affect the probability of ongoing employment for two quarters and do not facilitate transitions to direct-hire jobs. These results qualify the interpretation of a large experimental literature documenting the benefits of job placement services for labor market outcomes of low-skilled workers. We find that the benefits of job placements derive entirely from direct-hire jobs; placing low-skilled workers in temporary-help jobs is no more effective than providing no job placements at all.

Women, War and Wages: The Effect of Female Labor Supply on the Wage Structure at Mid-Century

This paper investigates the effects of female labor supply on the wage structure. To identify variation in female labor supply, we exploit the military mobilization for World War II, which drew many women into the workforce as males exited civilian employment. The extent of mobilization was not uniform across states, however, with the fraction of eligible males serving ranging from 41 to 54 percent. We find that in states with greater mobilization of men, women worked substantially more after the War and in 1950, though not in 1940. We interpret these differentials as labor supply shifts induced by the War. We find that increases in female labor supply lower female wages, lower male wages, and increase the college and premium and male wage inequality generally. Our findings indicate that at mid-century, women were closer substitutes to high school graduate and relatively low-skill males, but not to those with the lowest skills.

The Rise in Disability Recipiency and the Decline in Unemployment

Between 1984 and 2000, the share of non-elderly adults receiving benefits from the Social Security Disability Insurance (DI) and Supplemental Security Income (SSI) programs rose from 3.1 to 5.3 percent. We trace this growth to reduced screening stringency and, due to the interaction between growing wage inequality and a progressive benefits formula, a rising earnings replacement rate. We explore the implications of these changes for the level of labor force participation among the less skilled and their employment responses to adverse employment shocks. Following program liberalization in 1984, DI application and recipiency rates became two to three times as responsive to plausibly exogenous labor demand shocks. Contemporaneously, male and female high school dropouts became increasingly likely to exit the labor force rather than enter unemployment in the event of an adverse shock. The liberalization of the disability program appears to explain both facts. Accounting for the role of disability in inducing labor force exit among the low-skilled unemployed, we calculate that the U.S. unemployment rate would be two-thirds of a percentage point higher at present were it not for the liberalized disability system.

Journal of Economic Perspectives

This year marked the twenty-seventh volume of the Journal of Economic Perspectives. Throughout its history, the Journal has sought to contribute to the economics profession along multiple dimensions: introducing readers to state-of-the-art thinking on theoretical and empirical research topics; encouraging cross-fertilization of ideas among the fields of economics; providing analyses of public policy issues; providing readings for students; offering illustrations that are useful in lectures; sparking discussion among colleagues; suggesting directions for future research; and analyzing features of the economics profession itsel