Research

Published and Forthcoming Papers

With Pedro Bessone, Gautam Rao, Frank Schilbach, and Mattie Toma, QJE 136.3 (2021)
Abstract: The urban poor in developing countries face challenging living environments, which may interfere with good sleep. Using actigraphy to measure sleep objectively, we find that low-income adults in Chennai, India sleep only 5.5 hours per night on average despite spending 8 hours in bed. Their sleep is highly interrupted, with sleep efficiency—sleep per time in bed—comparable to those with disorders such as sleep apnea or insomnia. A randomized three-week treatment providing information, encouragement, and improvements to home sleep environments increased sleep duration by 27 minutes per night by inducing more time in bed. Contrary to expert predictions and a large body of sleep research, increased nighttime sleep had no detectable effects on cognition, productivity, decision-making, or well-being, and led to small decreases in labor supply. In contrast, short afternoon naps at the workplace improved an overall index of outcomes by 0.12 standard deviations, with significant increases in productivity, psychological well-being, and cognition, but a decrease in work time.

Data for this study is available here.

With Atheendar Venkataramani. PNAS 118.5 (2021)
Abstract: Poverty confers many costs on individuals, both through direct material deprivation and by reducing the mental bandwidth (cognitive resources) needed to engage meaningfully with life’s activities. We hypothesize that poverty may also reduce human welfare by decreasing the experiential value of what little the poor are able to consume – a de facto “tax” on consumption. We test this hypothesis using a randomized controlled trial in which we experimentally simulate key aspects of poverty via methods commonly used in laboratory studies (e.g. memorizing sequences) and via introducing stressors commonly associated with life in poverty (e.g. thinking about financial security and experiencing thirst). Participants then engaged in consumption activities and were asked to rate the value of these activities. Consistent with our hypothesis, the randomly assigned stressors reduced ratings of the consumption activities, with the strongest effects on the consumption of food. Our results shed new light on how the consequences of poverty on human welfare may compound. They may also change the calculus on appropriate policies to combat poverty, such as cash transfers.

Data for this study is available here.

Informing Sleep Policy through Field Experiments

With Susan Redline, Gautam Rao, Frank Schilbach, and Mattie Toma. Science 374.6567 (2021): 530-533
Please visit Mattie Toma’s website to download a copy of this article if you do not have access through your institution.

With Sendhil Mullainathan and Frank Schilbach, AER Papers and Proceedings (2016)

With George Lowenstein, Jessica Kopsic, and Kevin Volpp, Journal of Health Economics (2015)
Abstract: This study examines the impact of individually oriented, purely altruistic, and a hybrid of competitive and cooperative monetary reward incentives on older adults’ completion of cognitive exercises and cognitive function. We find that all three incentive structures approximately double the number of exercises completed during the six-week active experimental period relative to a no incentive control condition.However, the altruistic and cooperative/competitive incentives led to different patterns of participation,with significantly higher inter-partner correlations in utilization of the software, as well as greater persistence once incentives were removed. Provision of all incentives significantly improved performance on the incentivized exercises. However, results of an independent cognitive testing battery suggest no generalizable gains in cognitive function resulted from the training.

With Emma Dean and Frank Schilbach, In The Economics of Poverty Traps. University of Chicago Press. 2018. 
Abstract: This paper is a primer for economists interested in the relationship between poverty and cognitive function. We begin by discussing a set of underlying aspects of cognitive function relevant to economic decision-making — attention, inhibitory control, memory, and higher-order cognitive functions — including descriptions of validated tasks to measure each of these areas. Next, we review literature that investigates channels through which poverty might impact cognitive function and economic behavior, by discussing already existing knowledge as well as less well-researched areas that warrant further exploration. We then highlight ways in which the different aspects of cognitive function may impact economic outcomes, discussing both theoretical models and empirical evidence. Finally, we conclude with a discussion of open research questions and directions for future research.

With Christina Brown, Supreet Kaur, and Geeta Kingdon. QJE 2025
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 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 22% 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.

Working Papers

Abstract: Religion is an important force in many individuals’ lives, with approximately 85 percent of the world’s population expressing some religious belief. Yet, the literature on religion’s impact on economic outcomes remains relatively sparse, driven in part by challenges around identification. This paper explores one aspect of religion’s impact on economic outcomes by examining the impact of the observance of Ramadan on the economic output of farmers in India. The analysis leverages heterogeneity in cropping cycles between and within districts as well as the fact that Ramadan cycles throughout the calendar year to generate three sources of variation in the overlap between Ramadan and the labor-intensive portions of the cropping cycle. Using a difference-in-differences-in-differences approach, I find that overlap between Ramadan and the labor-intensive portions of cropping cycles results in declines in production which correspond to approximately one percent of agricultural GDP in India annually and a 20 to 40 percent decrease in productivity per fasting individual. These changes appear to be driven by changes in labor productivity and are not substantially compensated for via other potential margins of adjustment such as increased draft labor. Additional analyses suggest that productivity declines are likely to be driven primarily by reduced caloric intake rather than by other behavioral changes during Ramadan.

Covid-19 and Mental Health in India

With Simone Schaner and Jinkook Lee
Please email me if you would like a copy of the draft.

Ambient Air Temperature and Productivity and Learning at Work

With Pedro Bessone and Isadora Frankenthal
Abstract: We study the impact of temperature on productivity and productivity growth using detailed data from 452 Indian data-entry workers. A one degree Celsius increase in temperature increases breaks, lowering same-day productivity by 1.2%, without altering cognition or changes in hours or days worked. Beyond impacting the level of performance, higher temperatures also reduce the rate of productivity growth by 0.9 to 3.0 percentage points per degree Celsius over the past week. Our findings suggest a novel microfoundation for temperature’s impact on economic growth, with implications for developing countries facing rising temperatures, high workforce turnover, and increasingly knowledge-based economies.

Psychological Barriers to Participation in the Labor Market: Evidence from Rural Ghana

With Leandro Carvalho, Damien de Walque, Crick Lund, Vincent Somville and Jingyao Wei
Abstract: Mental health conditions are strongly associated with lower participation in the labor market. Yet, little is known about the channels through which such conditions impact labor supply and income. To shed light on this process, we decompose it and investigate the relationship between mental health conditions and (i) job take-up, (ii) labor supply, output, and income conditional on being willing to work, and (iii) quit rates. We do so by randomly offering high-paying jobs when little other work is available in a population living in poverty, with high levels of depression and anxiety. We find that people suffering from depression and anxiety are twice as likely to decline a work offer outside of the home, but equally likely to be willing to work from home. However, among the job-takers working from home, depression and anxiety do not predict the actual amount of work completed, labor income, or quit rates. These findings suggest that a key channel through which mental health impacts labor market outcomes may be one’s desire or willingness to work rather than performance on the job conditional on taking up work. Further, they suggest an important way to increase engagement with the labor market for those in poor mental health could be the provision of jobs that can be completed from home.
R&R at JDE

Habit Formation in Labor Supply

With Luisa Cefala, Supreet Kaur, and Yogita Shamdasani
Abstract: We examine the possibility of habit formation in labor supply. Using a field experiment
with casual urban laborers in India, we randomly provide treated workers with small financial
incentives for attendance over 7 weeks, leading to a 26% increase in labor supply. We then
test for the persistence of impacts after the incentives are removed. First, we see a persistent
18% increase in labor supply over the following 2 months, resulting in a 10% increase in
employment. Second, labor market disruptions deplete habit stock: shocks that temporar-
ily pull workers out of the labor market instantly eliminate persistence effects. Third, we
see no “fixed cost” changes in household time use, or learning among workers or employers—
consistent with true state-dependence in labor supply. Rather, workers self-report an increase
in automaticity—suggesting a change in their psychological default. Fourth, treated workers
exhibit a higher willingness to accept work contracts that are of longer duration and less
flexible. Fifth, employers accurately predict treatment effects, and prefer hiring workers who
have been treated with our habit stock intervention. Our results support the view that state-
dependence in labor supply has relevance for a variety of labor market phenomena. They
also suggest that intermittent employment and frequent shocks may inhibit low-income work-
ers from becoming habituated to regular work—with potential implications for absenteeism,
turnover, and the transition to formal employment in poor countries.

Psychological Barriers to Participation in the Labor Market: Evidence from Rural Ghana

With: Leandro Carvalho, Damien de Walque, Crick Lund, Vincent Somville, and Jingyao Wei
Abstract: Mental health conditions are strongly associated with reduced labor market participation, but the underlying channels through which such conditions impact labor supply remain unclear. We conduct a two-phase study decomposing this relationship by examining (i) job take-up decisions and (ii) labor supply, output, and earning conditional on job take-up, and (iii) quit rates. In Phase 1, women in rural Ghana are asked whether they would be willing to take-up a cash-for-work job during the lean season when alternative work is scarce. We find that individuals with depression and anxiety, which are common in this population, are much more likely to decline work offers outside the home but equally likely to accept work-from-home positions. In Phase 2, we randomly offer jobs at home to those who were willing to work from home, avoiding selection effects. Neither depression nor anxiety predict work completion, income, or quit rates. These findings suggest that poor mental health may harm labor market outcomes in traditional jobs outside of the home via reduced take-up, above and beyond the established negative impacts of mental health on productivity in work outside of the home. But, the results also suggest an alternative approach to improving labor market outcomes for those in poor mental health: work-from-home opportunities, which are not associated with lower take-up or lower productivity on the job for those in poor mental health.

Work in Progress

Loneliness and Migration
(with Achyuta Adhvaryu, Anant Nyshadham, Advait Rajagopal, Andelyn Russell, and Pedro Souza)