Michael Kremer, Dan Levy
Cited by*: 16 Downloads*: 9

This paper examines a natural experiment in which students at a large state university were randomly assigned roommates through a lottery system. We find that on average, males assigned to roommates who reported drinking in the year prior to entering college had one quarter-point lower GPA than those assigned to non-drinking roommates. The 10th percentile of their college GPA is half a point lower than among males assigned non-drinking roommates. For males who themselves drank frequently prior to college, assignment to a roommate who drank frequently prior to college reduces GPA by two-thirds of a point. Since students who drink frequently are particularly influenced by frequent-drinking roommates, substance-free housing programs could potentially lower average GPA by segregating drinkers. The effect of initial assignment to a drinking roommate persists and possibly even grows over time. In contrast, students' college GPA is not influenced by roommates' high school grades, admission test scores, or family background. Females' GPAs are not affected by roommates' drinking prior to college. Overall, these findings are more consistent with models in which peers change preferences than models in which they change endowments.
Johanne Boisjoly, Greg Duncan, Jacque Eccles, Michael Kremer, Dan Levy
Cited by*: 0 Downloads*: 9

Mixing across racial and ethnic lines could spur understanding or inflame tensions between groups. We find that white students at a large state university randomly assigned African American roommates in their first year were more likely to endorse affirmative action and view a diverse student body as essential for a high-quality education. They were also more likely to say they have more personal contact with, and interact more comfortably with, members of minority groups. Although sample sizes are too small to provide definitive evidence, these results suggest students become more empathetic with the social groups to which their roommates belong.
Mary Kay Gugerty, Michael Kremer
Cited by*: 1 Downloads*: 7

Many argue that organizations of the disadvantaged create positive externalities, and in particular strengthen the position of these groups in society. A natural inference is that these organizations should be subsidized. We argue that the benefits of expanding the operations of these groups must be set against the potential costs of weakening the role of the disadvantaged in these organizations. A prospective, randomized evaluation of a development program targeted at strengthening rural women's groups in western Kenya suggests that the program did not improve group strength or functioning as measured by participation rates, assistance to members, and assistance to other community projects. The funding did, however, change the very characteristics of the groups that made them attractive to funders in the first place. Younger, more educated women and women employed in the formal sector joined the groups, and men and better-educated and wealthier women moved into key leadership positions.
Michael Kremer, Edward Miguel
Cited by*: 1 Downloads*: 6

Intestinal helminths - including hookworm, roundworm, schistosomiasis, and whipworm - infect more than one-quarter of the world's population. A randomized evaluation of a project in Kenya suggests that school-based mass treatment with deworming drugs reduced school absenteeism in treatment schools by one quarter; gains are especially large among the youngest children. Deworming is found to be cheaper than alternative ways of boosting school participation. By reducing disease transmission, deworming creates substantial externality health and school participation benefits among untreated children in the treatment schools and among children in neighboring schools. These externalities are large enough to justify fully subsidizing treatment. We do not find evidence that deworming improves academic test scores. Existing experimental studies, in which treatment is randomized among individuals in the same school, find small and insignificant deworming treatment effects on education; however, these studies underestimate true treatment effects if deworming creates positive externalities for the control group and reduces treatment group attrition.