Non-market determinants of human capital accumulation: Theory and evidence.

摘要

Crime and reputation. A model of social interaction is developed in which individuals with varying payoffs from street crime meet in an environment with incomplete information. The value of a reputation for violence is demonstrated. Those who do not gain from street crime directly nevertheless invest in violence and thereby build a reputation that will earn them deference from the rest of the community. It may be that even when the fraction of the population with a direct interest in street crime is small a larger proportion will necessarily participate in violence in pursuit of reputation. Thus the model explains how a social force (reputation) can support an ‘underclass’ culture of violence in communities where the incentives for such behavior are otherwise weak. The model also reveals how the social structure of a community interacts with returns to crime to determine the value of a street reputation.; On the compassion of time-limited welfare programs ( with H. Fang). Supporters of recent welfare reforms argue that time limits and other eligibility restrictions serve recipients. We present a simple model of present-biased preferences to investigate the theoretical validity of this claim. We first identify four types of outcome that describe the behavior of a present-biased agent in the absence of time limits. We then show that the behavioral consequences of time limits are contingent on which outcome characterizes the agent's behavior in the absence of time limits. Under some conditions the imposition of time limits may improve the well-being of welfare recipients evaluated both in terms of long-run, time-consistent utility and the period-one self's utility. This benefit of time limits may come either from allowing the welfare eligible to start working earlier than they otherwise would or, contrary to the intent of the reforms, from allowing them to postpone working.; Time-inconsistency and welfare program participation: Evidence from the NLSY (with H. Fang). This paper applies a model of potentially time-inconsistent preferences to the problem of dynamic labor supply and welfare program participation. From panel data on the choices of single women with children, we provide estimates of the degree of time-inconsistency, and of its influence on the welfare take-up decision. Estimates of time-discount parameters suggest present-bias in preferences. Simulations of the estimated model indicate that, in states with relatively low welfare benefits, commitment problems lead to significant under-investment in human capital. However, policies such as welfare time limits and work requirements, that provide imperfect commitments to future human capital investment, appear unlikely to generate substantial utility gains for the welfare eligible.; The effect of adolescent experience on labor market outcomes: The case of height (with N. Persico and A. Postlewaite ). Consistent with prior studies, we find that taller workers receive a wage premium, and that the disparity in wages is similar in magnitude to the race and gender gaps. Our contribution is to exploit the variation in an individual's height over time to identify the channels through which height affects wages. We show that for white males, the effect of adult height is essentially eliminated when adolescent height is taken into account. We take this as evidence that adolescent height has important economic implications long after the time that it is observable to others, and we explore the channels through which the effects might be manifested.