In this paper, we use mobile messaging to leverage recipients' social ties and encourage offline prosocial activities in groups. In particular, we conduct a randomized field experiment with 80,000 blood donors and study how behavioral interventions and economic rewards motivate offline group...

A solution to marketplace information asymmetries is to have trading partners publicly rate each other post-transaction. Many have shown that these ratings are effective; we show that their effectiveness deteriorates over time. The problem is that ratings are prone to inflation, with raters...

Platform marketplaces can potentially steer buyers to certain sellers by recommending or guaranteeing those sellers. Money-back guarantees--which create a direct financial stake for the platform in seller performance--might be particularly effective at steering, as they align buyer and platform...

Shortage is common in many markets, such as those for human organs or blood, but the problem is often difficult to solve through price adjustment, given safety and ethical concerns. In this paper, we investigate whether market designers can use non-price methods to address shortage....