Published and Accepted Papers
Abstract: Schooling may build human capital not only by teaching academic skills, but by expanding the capacity for cognition itself. We focus specifically on cognitive endurance: the ability to sustain effortful mental activity over a continuous stretch of time. As motivation, we document that globally and in the US, the poor exhibit cognitive fatigue more quickly than the rich across a variety of field settings; they also attend schools that offer fewer opportunities to practice thinking for continuous stretches. Using a field experiment with 1,600 Indian primary school students, we randomly increase the amount of time students spend in sustained cognitive activity during the school day—using either math problems (mimicking good schooling) or non-academic games (providing a pure test of our mechanism). Each approach markedly improves cognitive endurance: students show 21% less decline in performance over time when engaged in intellectual activities—listening comprehension, academic problems, or IQ tests. They also exhibit increased attentiveness in the classroom and score higher on psychological measures of sustained attention. Moreover, each treatment improves students' school performance by 0.09 standard deviations. This indicates that the experience of effortful thinking itself—even when devoid of any subject content—increases the ability to accumulate traditional human capital. Finally, we complement these results with quasi-experimental variation indicating that an additional year of schooling improves cognitive endurance, but only in higher-quality schools. Our findings suggest that schooling disparities may further disadvantage poor children by hampering the development of a core mental capacity.
Abstract: Workers who are worried about their personal finances may find it hard to focus at work. If so, financial concerns by themselves could hinder productivity. We test this hypothesis in a sample of low-income Indian piece rate manufacturing workers. We stagger when wages are paid out: some workers are paid earlier and receive a cash infusion while others remain liquidity constrained. They use the cash to immediately pay off debts and buy household essentials, addressing their financial concerns. Subsequently, they become more productive at work: their output increases by 7.1% (0.12 SDs), and they make fewer costly, unintentional mistakes. Workers with more cash-on-hand thus not only work faster but also more attentively, suggesting improved cognition. These effects are concentrated among more financially constrained workers. We argue that mechanisms such as gift exchange or nutrition cannot account for our results. Instead, our findings suggest that financial strain, at least partly through psychological channels, has the potential to reduce earnings exactly when money is most needed.
Abstract: This paper measures excess labor supply in equilibrium. We induce hiring shocks—which employ 24% of the labor force in external month-long jobs—in Indian local labor markets. In peak months, wages increase instantaneously and local aggregate employment declines. In lean months, consistent with severe labor rationing, wages and aggregate employment are unchanged, with positive employment spillovers on remaining workers—indicating that over a quarter of labor supply is rationed. At least 24% of lean self-employment among casual workers occurs because they cannot find jobs. Consequently, traditional survey approaches mismeasure labor market slack. Rationing has broad implications for labor market analysis.
Abstract: This paper develops a new approach to test for downward wage rigidity by examining transitory shocks to labor demand (i.e., rainfall) across 600 Indian districts. Nominal wages rise during positive shocks but do not fall during droughts. In addition, transitory positive shocks generate ratcheting: after they have dissipated, wages do not adjust back down. Ratcheting reduces employment by 9 percent, indicating that rigidities distort employment levels. Inflation, which is unaffected by local rainfall, enables downward real wage adjustments—offering causal evidence for its labor market effects. Surveys suggest that individuals believe nominal wage cuts are unfair and lead to effort reductions.
Abstract: Relative pay concerns have potentially broad labor market implications. In a month-long experiment with Indian manufacturing workers, we randomize whether coworkers within production units receive the same flat daily wage or differential wages according to their (baseline) productivity ranks. When co-workers’ productivity is difficult to observe, pay inequality reduces output by 0.45 standard deviations and attendance by 18 percentage points. It also lowers co-workers’ ability to cooperate in their own selfinterest. However, when workers can clearly perceive that their higher paid peers are more productive than themselves, pay disparity has no discernible effect on output, attendance, or group cohesion.
Abstract: Workers with self-control problems do not work as hard as they would like. This changes the logic of agency theory by partly aligning the interests of the firm and worker: both now value contracts that elicit more effort in the future. Three findings from a year-long field experiment with data entry workers suggest the quantitative importance of self control at work. First, workers choose dominated contracts—which penalize low output but provide no greater reward for high output—36% of the time to motivate their future selves; use of these contracts increases output by the same amount as an 18% increase in the piece-rate. Second, effort increases as the (randomly assigned) payday gets closer: output rises 8% over the pay week; calibrations show that justifying this would require a 4% daily exponential discount rate. Third, for both findings there is significant and correlated heterogeneity: workers with larger payday effects are both more likely to choose dominated contracts and show greater output increases under them. This correlation grows with experience, consistent with the hypothesis that workers learn about their self-control problems over time. Self-control problems among workers could potentially lead firms to either adopt high-powered incentives or impose work rules to allow monitoring of worker effort.
“Self-Control and the Development of Work Arrangements” (with Michael Kremer and Sendhil Mullainathan), American Economic Review Papers and Proceedings, 2010. 100(2): pp. 624-628.