The recent expansion of health-plan choice has been touted as increasing competition and enabling people to choose plans that fit their needs. This study provides new evidence challenging these proposed benefits of expanded health-insurance choice. We examine health-insurance decisions of...

A large literature treats take-up of commitment contracts, in the form of choice-set restrictions or penalties, as a smoking gun for time-inconsistency or self-control problems (for short, "present focus"). This paper develops techniques for inspecting this assumption, presents new...

We conducted a randomized controlled trial testing the effect of modest incentives to attend the gym among new members of a fitness facility, a population that is already engaged in trying to change a health behavior. Our experiment randomized 836 new members of a private gym into a control...

Despite the successes of automatic enrollment (AE) in raising participation, a significant share of 401(k) enrollees remain at-risk for retirement insecurity. We assert that this risk may be shaped by an employee's initial decision to either confirm enrollment at the default rate or to...

The link between cell phone use while driving and crash risk has in recent years become an area of active research. The most notable of the over 125 studies has concluded that cell phones produce a four-fold increase in relative crash risk--comparable to that produced by illicit levels of...

Economists have advanced several psychological frictions to explain why many 401(k)-eligible employees undersave for retirement despite generous matching incentives. We provide evidence on four of these frictions through a field experiment randomizing undersaving employees to information- and...

Given its importance for theory, welfare, and policy, economists have long sought to understand the prevalence of and motives for risk aversion in the field. In practice, this inquiry is often confounded by the potential for biased beliefs (e.g., betting, investing), imperfect understanding...

We analyze the offering, asking, and granting of help or other benefits as a three-stage game with bilateral private information between a person in need of help and a potential help-giver. Asking entails the risk of rejection, which can be painful: since unawareness of the need can no longer be...