Arbitrary clock conventions – by generating large differences in when the sun sets across locations – help determine the geographic distribution of educational attainment levels; greater effect is among the poor

Poor Sleep: Sunset Time and Human Capital Production. Maulik Jagnani. Jan 15 2019. https://www.dropbox.com/s/5ojttz8d9leco4n/jagnani_jmp.pdf

Abstract: This paper provides evidence that arbitrary clock conventions – by generating large differences in when the sun sets across locations – help determine the geographic distribution of educational attainment levels. I show later sunset reduces children’s sleep: when the sun sets later, children go to bed later; by contrast, wake-up times do not respond to solar cues. Sleep-deprived students decrease study effort, consistent with a model where sleep is productivity-enhancing and increases the marginal returns of effort. Overall, school-age children exposed to later sunsets attain fewer years of education and  are less likely to complete primary and middle school. Later sunsets are also associated with fewer hours of sleep and lower wages among adults. The non-poor adjust their sleep schedules when the sun sets later; sunset-induced sleep deficits are most pronounced among the poor, especially in periods when households face severe financial constraints.

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I find that later sunset causes school-age children to begin sleep later, but does not affect wake-up times. An hour (approximately two standard deviation) delay in sunset time reduces children’s sleep by 30 minutes. I also show that later sunset reduces students’ time spent on homework or studying, and time spent on formal and informal work by child laborers,while increasing time spent on indoor leisure for all children. This result is consistent with a model where sleep is productivity-enhancing and increases the marginal returns of study effort for students and work effort for child laborers.

The second part of the paper examines the consequent lifetime impacts of later sunset on stock indicators of children’s academic outcomes. I use nationally-representative data from the 2015 India Demographic and Health Survey (DHS) to estimate how children’s education outcomes co-vary with annual average sunset time across eastern and western locations within a district. I find that an hour (approximately two standard deviation) delay in annual average sunset time reduces years of education by 0.8 years, and children in geographic locations with later sunset are less likely to complete primary and middle school.