We use a large-scale personalized field experiment on Wikipedia to examine the effect of motivation on the contributions of domain experts to public goods. Our baseline positive response rate is 45%. Furthermore, experts are 13% more interested in contributing when we mention the private benefit of contribution, such as the likely citation of their work. In the contribution stage, using a machine learning model, we find that greater matching accuracy between a recommended Wikipedia article and an expert’s paper abstract, together with an expert’s reputation and the mentioning of public acknowledgement, are the most important predictors of both contribution length and quality. Our results show the potential of scalable personalized interventions using recommender systems to study drivers of prosocial behavior.

This paper presents an empirical framework to study the assignment of children into foster homes and its implications on placement outcomes. The empirical application uses a novel dataset of confidential foster care records from Los Angeles County, CA. The estimates of the empirical model are used to examine policy interventions aimed at improving placement outcomes. In general, it is observed that market thickness tends to improve expected placement outcomes. If placements were assigned across all the administrative regions of the county, the model predicts that (i) the average number of foster homes children go through before exiting foster care would decrease by 8% and (ii) the distance between foster homes and children’s schools would be reduced by 54%.

We examine the potential of healthy food subsidies for reducing nutritional inequality through demand-side interventions. Using a pre-registered field experiment with low-income grocery shoppers, we show that low-cost, scalable behavioral interventions make subsidies substantially more effective. Our unique design allows us to elicit choices and deliver subsidies both before and during a shopping trip. We examine two novel interventions: giving shoppers greater agency through a choice between subsidies and introducing waiting periods designed to prompt deliberation about food purchases. The interventions increase healthy purchases by 61% relative to choiceless healthy subsidies, and 199% relative to a control group.

Of the 650,000 individuals released annually from prisons, two-thirds are re-arrested within three years. Many struggle to fulfill basic needs or associate with new peers. Programs that offer "aftercare services", a comprehensive menu of supportive services (e.g. housing, transportation, job counseling, peer support groups, etc), are potentially important. We partner with an aftercare service provider in Pittsburgh and conduct an RCT where participants are incentivized to use their services at various intensities, i.e. 3 or 5 visits, to receive a reward. The intervention increased visits relative to the control group, and the composition of services used evolved from basic needs to employment and group support as the number of visits increased. However, meeting the 3-visit goal is attainable, whereas participants give up trying to visit 5 times. This is reflected in preliminary results on re-arrests. Modest encouragement is more successful at reducing recidivism.