Iran has the world's only government-regulated kidney market. We report the results of the first field study of donor behaviour in this unusual market. Participants have lower risk tolerance and higher patience levels than the Iranian average but display no difference in rationality from...

We identify the ages that constitute critical periods in children's development towards their adult health status. For this we use data on families migrating into Sweden from countries that are mostly poorer, with less healthy conditions. Long-run health is proxied by adult height. The relation...

This paper provides an empirical test of the rational addiction model, used in economics to model individuals' consumption of addictive substances, versus the utility misprediction model, used in psychology to explain the discrepancy between people's decision and their subsequent experiences. By...

Time scarcity is one of the strongest correlates of fast food consumption. To estimate the causal effect of time lost on food choice, we match daily store-specific foot traffic data traced via smartphones to plausibly exogenous shocks in highway traffic data in Los Angeles. We find that on days...

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...

This paper examines the long-term impacts on health and healthy behaviors of two of the oldest and most widely cited U.S. early childhood interventions evaluated by the method of randomization with long-term follow-up: the Perry Preschool Project (PPP) and the Carolina Abecedarian Project (ABC)....

We present a field experiment to study the effects of non-monetary incentives on healthy food choices of 282 children in elementary schools. Previous interventions have typically paid participants for healthy eating, but this often may not be feasible. We introduce a system where food items are...

This paper investigates the role of biased health perceptions as driving forces of risky health behavior. We define absolute and relative health perception biases, illustrate their measurement in surveys and provide evidence on their relevance. Next, we decompose the theoretical effect into its...

Lack of information about COVID-19 and its spread may have contributed to excess mortality at the pandemic's onset. In April and May 2020, we implemented a randomized controlled trial with more than 3,000 households in 150 Bangladeshi villages. Our one-to-one information campaign via phone...

We find a strong relationship between risk-loving preferences and cognitive ability which becomes stronger as adherence to the generalized axiom of revealed preference (a proxy for rationality) increases. Our results are taken from a field study of individuals at the very bottom of the income...