In a study published in the Journal of Health Economics this year, George Loewenstein, Joseph Price and Kevin Volpp presented findings from a field experiment testing whether short-run incentives can create habit formation in children. Over a 3- or 5-week period, students received an incentive for eating a serving of fruits or vegetables during lunch. The study found that providing small incentives doubled the fraction of children eating at least one serving of fruits or vegetables. Two months after the end of the intervention, the consumption rate at schools remained 21% above baseline for the 3-week treatment and 44% above baseline for the 5-week treatment. These findings indicate that short-run incentives can produce changes in behavior that persist after incentives are removed.