The authors designed and tested a voluntary commitment product to help smokers quit smoking. The product (CARES) offered smokers a savings account in which they deposit funds for six months, after which they take a urine test for nicotine and cotinine. If they pass, their money is returned;...

There is growing interest in using messaging to drive prosocial behaviors, which contribute to investment in public goods. The authors worked with a leading nongovernmental organization in Peru to randomize nine different prorecycling messages that were crafted on the basis of best practices,...

Information asymmetries are important in theory but difficult to identify in practice. We estimate the empirical importance of adverse selection and moral hazard in a consumer credit market using a new field experiment methodology. We randomized 58,000 direct mail offers issued by a major South...

Numerous laboratory studies report on behaviors inconsistent with rational economic models. How much do these inconsistencies matter in natural settings, when consumers make large, real decisions and have the opportunity to learn from experiences? We report on a field experiment designed to...