Fatih Karahan

Unemployment Benefits and Unemployment in the Great Recession: The Role of Macro Effects

Equilibrium labor market theory suggests that unemployment benefit extensions affect unemployment by impacting both job search decisions by the unemployed and job creation decisions by employers. The existing empirical literature focused on the former effect only. We develop a new methodology necessary to incorporate the measurement of the latter effect. Implementing this methodology in the data, we find that benefit extensions raise equilibrium wages and lead to a sharp contraction in vacancy creation, employment, and a rise in unemployment.

What Do Data on Millions of U.S. Workers Reveal about Life-Cycle Earnings Risk?

We study individual earnings dynamics over the life cycle using panel data on millions of U.S. workers. Using nonparametric methods, we first show that the distribution of earnings changes exhibits substantial deviations from lognormality, such as negative skewness and very high kurtosis. Further, the extent of these nonnormalities varies significantly with age and earnings level, peaking around age 50 and between the 70th and 90th percentiles of the earnings distribution. Second, we estimate nonparametric impulse response functions and find important asymmetries: positive changes for high-income individuals are quite transitory, whereas negative ones are very persistent; the opposite is true for low-income individuals. Third, we turn to long-run outcomes and find substantial heterogeneity in the cumulative growth rates of earnings and total years individuals spend nonemployed between ages 25 and 55. Finally, by targeting these rich sets of moments, we estimate stochastic processes for earnings that range from the simple to the complex. Our preferred specification features normal mixture innovations to both persistent and transitory components and includes long-term nonemployment shocks with a realization probability that varies with age and earnings.

On the Persistence of Income Shocks Over the Life Cycle: Evidence and Implications

This paper proposes a novel specification for residual earnings that allows for a lifetime profile in the persistence and variance of labor income shocks. We show theoretically that the statistical model is identified and estimate it using data from the PSID. We strongly reject the hypothesis of a flat life-cycle profile for persistence and variance of persistent shocks, but not for the variance of transitory shocks. Shocks to earnings are only moderately persistent (around 0.75) for young individuals. Persistence rises with age up to unity until midway in life and decreases to around 0.95 toward the end of the life cycle. On the other hand, the variance of persistent shocks exhibits a U-shaped profile over the life cycle (with a minimum of 0.01 and a maximum of 0.045). Our estimate of persistence, for most of the working life, is substantially lower than typical estimates in the literature. We investigate the implications of these profiles for consumption-savings behavior with a standard life-cycle model. Under natural borrowing limits, the welfare cost of idiosyncratic risk implied by the age dependent income process is 32% lower compared to an AR(1) process without age profiles. This is mostly due to a higher degree of consumption insurance for young workers, for whom persistence is moderate. The results hold qualitatively for an economy with no borrowing, although the difference between specifications is smaller (23%). We conclude that the welfare cost of idiosyncratic risk is overstated.

Geographical Reallocation and Unemployment during the Great Recession: The Role of the Housing Bust

This paper quantitatively evaluates the hypothesis that the housing bust in 2007 decreased geographical reallocation and increased the dispersion and level of unemployment during the Great Recession. We construct an equilibrium model of multiple locations with frictional housing and labor markets. When house prices fall, the amount of home equity declines, making it harder for homeowners to afford the down payment on a new house after moving. Consequently, the decline in house prices reduces migration and causes unemployment to rise differently in different locations. The model accounts for 90 percent of the increase in geographical dispersion of unemployment and the entire decline in net migration. However, despite large effects on migration and geographical dispersion of unemployment, the effect on aggregate unemployment is moderate: Our findings suggest that, absent the housing bust, aggregate unemployment would have been 0.5 percentage point lower.

Population Aging, Migration Spillovers and the Decline in Interstate Migration

Interstate migration in the United States has declined by 50 percent since the mid-1980s. This paper studies the role of the aging population in this long-run decline. We argue that demographic changes trigger a general equilibrium effect in the labor market, which affects the migration rate of all workers. We document that an increase in the share of middle-aged workers (those ages 40 to 60) in the working-age population in one state causes a large fall in the migration rate of all workers in that state, regardless of their age. To understand this finding, we develop an equilibrium search model of many locations populated by workers whose moving costs differ. Firms prefer hiring local workers with high moving costs as they command lower wages due to their lower outside option. An increase in the share of middle-aged workers causes firms to recruit more from the local labor market instead of hiring from other locations, which increases the local job-finding rate and reduces everyone’s migration rate (“migration spillovers”). Our model reproduces remarkably well several cross-sectional facts between population flows and the age structure of the labor force. Our quantitative analysis suggests that population aging accounts for about half of the observed decline, of which 75 percent is attributable to the general equilibrium effect.

On the Persistence of Income Shocks over the Life Cycle: Evidence, Theory, and Implications,Second Version

How does the persistence of earnings change over the life cycle? Do workers at different ages face the same variance of idiosyncratic shocks? This paper proposes a novel specification for residual earnings that allows for an age profile in the persistence and variance of labor income shocks. We show that the statistical model is identified and estimate it using PSID data. We find that shocks to earnings are only moderately persistent (around 0:75) for young workers. Persistence rises with age up to unity until midway in life. The variance of persistent shocks exhibits a U-shaped profile over the life cycle (with a minimum of 0:01 and a maximum of 0:05). These results suggest that the standard specification in the literature (with constant persistence and variances) cannot capture the earnings dynamics of young workers. We also argue that a calibrated job turnover model can account for these non-at profiles. The key idea is that workers sort into better jobs and settle down as they age; in turn, magnitudes of wage growth rates decline, thereby decreasing variance of shocks. Furthermore the decline in job mobility results in higher persistence. Finally, we investigate the implications of age profiles for consumption-savings behavior. The welfare cost of idiosyncratic risk implied by the age-dependent income process is 34 percent lower compared with its age-invariant counterpart. This difference is mostly due to a higher degree of consumption insurance for young workers, for whom persistence is moderate. These results suggest that age profilles of persistence and variances should be taken into account when calibrating life-cycle models.

The Role of Start-Ups in Structural Transformation

The U.S. economy has been going through a striking structural transformation—the secular reallocation of employment across sectors—over the past several decades. We propose a decomposition framework to assess the contributions of various margins of firm dynamics to this shift. Using firm-level data, we find that at least 50 percent of the adjustment has been taking place along the entry margin, owing to sectors receiving shares of start-up employment that differ from their overall employment shares. The rest is mostly the result of life cycle differences across sectors. Declining overall entry has a small but growing effect of dampening structural transformation.