In a centralized marketplace that was designed to be simple, we identify participants whose choices are dominated. Using administrative data from Hungary, we show that college applicants make obvious mistakes: they forgo the free opportunity to receive a tuition waiver worth thousands of...

Often market designers cannot force agents to join a marketplace rather than using preexisting institutions. We propose a new desideratum for marketplace design that guarantees the safety of participation: Dominant Individual Rationality (DIR). A marketplace is DIR if every pre-existing strategy...