From 1960 to 2004, the rate of obesity in the United States increased from approximately 13% to 31%.¹ In 2004, 71% of US adults were overweight or obese according to standard definitions,² and at present obesity falls just behind smoking as a preventable cause of premature death.³ New strategies are needed to help reduce the rate of obesity in the US population.

Smoking is the leading preventable cause of premature death in the United States. Previous studies of financial incentives for smoking cessation in work settings have not shown that such incentives have significant effects on cessation rates, but these studies have had limited power, and the incentives used may have been insufficient.

Many Americans fail to get life-saving vaccines each year, and the availability of a vaccine for COVID-19 makes the challenge of encouraging vaccination more urgent than ever. We present a large field experiment ( N = 47,306) testing 19 nudges delivered to patients via text message and designed to boost adoption of the influenza vaccine. Our findings suggest that text messages sent prior to a primary care visit can boost vaccination rates by an average of 5%. Overall, interventions performed better when they were 1) framed as reminders to get flu shots that were already reserved for the patient and 2) congruent with the sort of communications patients expected to receive from their healthcare provider (i.e., not surprising, casual, or interactive). The best-performing intervention in our study reminded patients twice to get their flu shot at their upcoming doctor’s appointment and indicated it was reserved for them. This successful script could be used as a template for campaigns to encourage the adoption of life-saving vaccines, including against COVID-19.

Widespread concern about the number of deaths in US hospitals from medical errors¹ prompted the Accreditation Council for Graduate Medical Education (ACGME) to implement duty hour regulations effective July 1, 2003, for all ACGME-accredited residency programs.^2,3 Work limitations for residents included no more than 80 hours per week, with 1 day in 7 free of all duties, averaged over 4 weeks; no more than 24 continuous hours with an additional 6 hours for education and transfer of care; in-house call no more frequently than every third night; and at least 10 hours of rest between duty periods.²

The Accreditation Council for Graduate Medical Education (ACGME) implemented duty hour regulations on July 1, 2003, for all ACGME-accredited residency programs,^1,2 following concern about deaths associated with medical errors in US hospitals.³ These regulations limited the number of work hours per week, the number of continuous work hours, and the frequency of in-house call, and provided for a minimum amount of time between duty periods and days free of work duties.¹

We introduce and evaluate the effectiveness of temptation bundling—a method for simultaneously tackling two types of self-control problems by harnessing consumption complementarities. We describe a field experiment measuring the impact of bundling instantly gratifying but guilt-inducing “want” experiences (enjoying page-turner audiobooks) with valuable “should” behaviors providing delayed rewards (exercising). We explore whether such bundles increase should behaviors and whether people would pay to create these restrictive bundles. Participants were randomly assigned to a full treatment condition with gym-only access to tempting audio novels, an intermediate treatment involving encouragement to restrict audiobook enjoyment to the gym, or a control condition. Initially, full and intermediate treatment participants visited the gym 51% and 29% more frequently, respectively, than control participants, but treatment effects declined over time (particularly following Thanksgiving). After the study, 61% of participants opted to pay to have gym-only access to iPods containing tempting audiobooks, suggesting demand for this commitment device. This paper was accepted by Uri Gneezy, behavioral economics.