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.

Working Papers

Cognitive Endurance as Human Capital

With Christina Brown, Supreet Kaur, and Geeta Kingdon
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.
Note: Conditionally accepted at QJE.

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.

Work in Progress

Promoting Regular Labor Supply among the Urban Poor
(With Luisa Cefala, Supreet Kaur, and Yogita Shamdasani)

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