Even though the opioid epidemic is a major concern in many countries, medication assisted treatment is underused. We conduct a randomized controlled trial to study the effectiveness of two interventions for encouraging adherence to a Methadone Maintenance Treatment (MMT), and its subsequent impact on patients’ health and their relationships with family. The first intervention (T1) provides cash incentives for individual attendance. We find that, while they are in place, these incentives increase MMT attendance and health, but their impact does not last beyond the duration of the incentives. For the second intervention (T2), individuals are randomly assigned to a eight member team, and provided a cash incentive of the same magnitude in T1, but paid conditional on average team (rather than individual) attendance. Team members are unknown to each other, and never interact. For individuals in T2, the incentive to attend is about 1 8 th than in T1, but in turn they are able to identify as being part of a team and contribute to a common goal. Remarkably, the impact of T2 on attendance is almost a large as that of T1. Furthermore, among participants in T2, those who were told they belonged to an above average attendance team reacted more to the intervention than those told they were in a below average attendance team. Belonging to a (good) team may give individuals an identity based motive to attend MMT treatment, and induces them to contribute effort for the benefit of other team members.

According to UNESCO, one-third of the world’s youths are victims of bullying, which deteriorates academic performance and mental health, and increases suicide ideation and the risk of committing suicide. This paper analyzes a four-month parent-directed intervention de- signed to foster empathy in middle schoolers in China. Our implementation and evaluation study enrolled 2,246 seventh and eighth graders and their parents, whom we assigned, at the classroom level, to the control or intervention condition randomly. We measured, before and after the in- tervention, parental investments, children’s empathy, and self-reported bullying perpetration and victimization incidents. Our analyses show that, in the short run, the intervention increased invest- ments and empathy. More importantly, the program also indirectly reduced bullying incidents. In the longer run, additional evidence suggests that the reduction in bullying persisted for one year. The program also moved up treated students’ percentile rank in the high school entrance exam by 1.4 in two years. We measured costs and found that it costs $16.30 for our intervention to reduce one bullying incident. Our study offers a scalable and low-cost strategy that can inform public policy on bullying prevention in other similar settings.

This paper examines the impact of a randomized experiment in Macedonia in which program applicants were assigned to receive a job interview and the employers were subsidized when job and worker were matched. The interview led to more than 25 percentage point increase in employment in the first 6 months, and the average effect persists, at around 15 percentage points after the subsidies has expired.

Bullying is on the rise among young people but the cause is unknown. This paper provides a first empirical study on the cause of being a bully by focusing on the within-class socioeconomic status (SES) inequality.

This paper examines whether the negative effects of leaving children behind (LBCs) spillover to other students' outcomes in the classroom. Using Chinese samples where students were randomly assigned to classes in the 7th grade, I show negative peer effects appear in 10 weeks.  

The phenomenon of parents’ Middle-School Blues is widespread yet often overlooked. We find that parental mental health is “V-shaped” throughout children’s developmental stages, reaching its nadir during middle school. We then leverage data from a four-month parental involvement program on empathy and positive parenting. We find the program has a significant positive effect on parental mental health, measured by GHQ-12 score, by 0.17 standard deviation. The effect is large enough to help parents combat Middle-School Blues. We attribute the program’s effect on mental health to the improvement in parental skills, time inputs, and children’s non-cognitive ability. The mediation analysis suggests that these three factors interact and account for over 62% of the total program effects, and that the improvement in parental skills is the key driver of promoting parental mental health.

In many societies, parents prefer sons over daughters, but the well-being effects of child gender, especially in later life, are less studied. Using the latest two waves of the China Health and Retirement Longitudinal Study (CHARLS), this paper evaluates the impacts of having daughters on older parents' subjective well-being (SWB) in China, which has a rapidly aging population and the traditional preference for sons. Studying the cohort of parents whose child gender is as good as random, we find that having more daughters promotes older parents' SWB, especially overall life satisfaction, satisfaction with health, and satisfaction with children. Our results suggest that the increase in SWB is achieved through better health, more financial support from daughters, more spending on leisure and a lower probability of working. The positive SWB effects of daughters are found to be more salient among more vulnerable groups, including those who are older, less educated, and with fewer children. 

We are in a youth mental health crisis. How can we help? In this trial, we educate more than 3500 middle school parents to learn about students' ability and interests by sending information about multiple intellegence and students' interests. We find large gap between parental beliefs and children's beliefs. Simple treatment help parents understand children more, which lowers excessive parental expectation, subsequently reduce the children's stress and mental health problem. 

Is the rising perceived cost of childrearing discouraging fertility? How do people’s fertility plans respond to potential fertility subsidies? In two separate large field survey experiments in China, we answer both questions and propose potential interventions for boosting fertility in developing countries. Interestingly, we find that people with one or no child expect high costs of a second or third child, while people with more than one child manage to raise children inexpensively. TOT estimates show that a higher perceived cost of child leads to lower birth planning, suggesting that the high perceived cost for the low-birth population partially contributes to the low fertility rate.