Sleep: Educational Impact and Habit Formation
There is growing evidence on the importance of sleep for productivity, but little is known about the impact of interventions targeting sleep. In a field experiment among U.S. university students, we show that incentives for sleep increase both sleep and academic performance. Motivated by theories of cue-based habit formation, our primary intervention couples personalized bedtime reminders with morning feedback and immediate rewards for sleeping at least seven hours on weeknights. The intervention increases the share of nights with at least seven hours of sleep by 26 percent and average weeknight sleep by an estimated 19 minutes during a four-week treatment period, with persistent effects of about eight minutes per night during a one to five-week post-treatment period. Comparisons to secondary treatments show that immediate incentives have larger impacts on sleep than delayed incentives or reminders and feedback alone during the treatment period, but do not have statistically distinguishable impacts on longer-term sleep habits in the post-treatment period. We estimate that immediate incentives improve average semester course performance by 0.075--0.088 grade points, a 0.10--0.11 standard deviation increase. Our results demonstrate that incentives to sleep can be a cost-effective tool for improving educational outcomes.