On-the-Job Search and Precautionary Savings: Theory and Empirics of Earnings and Wealth Inequality

Abstract

In this paper, I develop and estimate a model of the labor market that can account for both the inequality in earnings and the much larger inequality in wealth observed in the data. I show that an equilibrium model of on-the-job search, augmented to account for saving decisions of workers, provides a direct and intuitive link between the empirical earnings and wealth distributions. The mechanism that generates the high degree of wealth inequality in the model is the dynamic of the “wage ladder” resulting from the search process. There is an important asymmetry between the incremental wage increases generated by on-the-job search (climbing the ladder) and the drop in income associated with job loss (falling off the ladder). The behavior of workers in low paying jobs is primarily governed by the expectation of wage growth, while the behavior of workers near the top of the distribution is driven by the possibility of job loss. This feature of the model generates differential savings behavior at different points in the earnings distribution. The wage growth expected by low wage workers, combined with the fact that their earnings are not much higher than unemployment benefits, causes them to dis-save. As a worker’s wage increases, the incentive to save increases: the potential for wage growth declines and it becomes increasingly important to insure against the large income reduction associated with job loss. The fact that high wage and low wage workers have such different savings behavior generates an equilibrium wealth distribution that is much more unequal than the equilibrium wage distribution. I estimate the structural parameters of the model by simulation-based methods using the 1979 youth cohort of the NLSY. The estimates indicate that the micro-level search and savings behavior—estimated from the dynamics of individuals’ labor market histories and wealth accumulation decisions—aggregates to replicate the cross-sectional inequality in earnings and wealth for this cohort.