Knowledge that Transforms

This paper uses the randomization of families to child protection investigators to estimate causal effects of foster care on adult crime. The analysis uses a new data set that links criminal justice data to child protection data in Illinois, and I find that investigators affect foster care placement. Children on the margin of placement are found to be two to three times more likely to enter the criminal justice system as adults if they were placed in foster care. One innovation describes the types of children on the margin of placement, a group that is more likely to include African Americans, girls, and young adolescents.

Management for helpful comments. We also thank Nick Kennedy, Stephen Wilson, Laura Dutson, Matthew Healey, Meng Ning, Courtney Stone, and Bennett Surajat for excellent research assistance. We are grateful to BoardEx and Linda Cechova for providing firm board data, Morningstar and Annette Larson for providing mutual fund data, and to the Chicago GSB Initiative on Global Markets for financial support. This paper uses social networks to identify information transfer in security markets. We focus on connections between mutual fund managers and corporate board members via shared education networks. We find that portfolio managers place larger bets on firms they are connected to through their network, and perform significantly better on these holdings relative to their non-connected holdings. A replicating portfolio of connected stocks outperforms a replicating portfolio of non-connected stocks by up to 7.8 % per year. Returns are concentrated around corporate news announcements, consistent with mutual fund managers gaining an informational advantage through the education networks. Our results

This paper presents new evidence on why unemployment insurance (UI) benefits affect search behavior and develops a simple method of calculating the welfare gains from UI using this evidence. I show that 60 percent of the increase in unemployment durations caused by UI benefits is due to a "liquidity effect" rather than distortions on marginal incentives to search ("moral hazard") by combining two empirical strategies. First, I find that increases in benefits have much larger effects on durations for liquidity-constrained households. Second, lump-sum severance payments increase durations substantially among constrained households. I derive a formula for the optimal benefit level that depends only on the reduced-form liquidity and moral hazard elasticities. The formula implies that the optimal UI benefit level exceeds 50 percent of the wage. The "exact identification" approach to welfare analysis proposed here yields robust optimal policy results because it does not require structural estimation of primitives.

The well-known association between height and earnings is often thought to reflect factors such as self esteem, social dominance, and discrimination. We offer a simpler explanation: height is positively associated with cognitive ability, which is rewarded in the labor market. Using data from the US and the UK, we show that taller children have higher average cognitive test scores, and that these test scores explain a large portion of the height premium in earnings. Children who have higher test scores also experience earlier adolescent growth spurts, so that height in adolescence serves as a marker of cognitive ability.

This paper constructs a model of non-balanced economic growth. The main economic force is the combination of differences in factor proportions and capital deepening. Capital deepening tends to increase the relative output of the sector with a greater capital share, but simultaneously induces a reallocation of capital and labor away from that sector. We first illustrate this force using a general two-sector model. We then investigate it further using a class of models with constant elasticity of substitution between two sectors and Cobb-Douglas production functions in each sector. In this class of models, non-balanced growth is shown to be consistent with an asymptotic equilibrium with constant interest rate and capital share in national income. We also show that for realistic parameter values, the model generates dynamics that are broadly consistent with US data. In particular, the model generates more rapid growth of employment in less capital-intensive sectors, more rapid growth of real output in more capital-intensive sectors and aggregate behavior in line with the Kaldor facts. Finally, we construct and analyze a model of "non-balanced endogenous growth," which extends the main results of the paper to an economy with endogenous anddirected technical change. This model shows that equilibrium will typically involve endogenous non-balanced technological progress.