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Can Social Contact Reduce Prejudice and Discrimination? Evidence from a Field Experiment in Nigeria


Can positive social contact between members of antagonistic groups reduce prejudice and discrimination? Despite extensive research on social contact, observational studies are difficult to interpret because prejudiced people may select out of contact with out-group members. We overcome this problem by conducting an education-based, randomized field experiment—the Urban Youth Vocational Training program (UYVT)—with 849 randomly sampled Christian and Muslim young men in riot-prone Kaduna, Nigeria. After sixteen weeks of positive intergroup social contact, we find no changes in prejudice, but heterogeneous-class subjects discriminate significantly less against out-group members than subjects in homogeneous classes. We trace this finding to increased discrimination by homogeneous-class subjects compared to non-UYVT study participants, and we highlight potentially negative consequences of in-group social contact. By focusing on skill-building instead of peace messaging, our intervention minimizes reporting bias and offers strong experimental evidence that intergroup social contact can alter behavior in constructive ways, even amid violent conflict.

Corresponding author
Alexandra Scacco is a Research Scientist, WZB Berlin Social Science Center, Reichpietschufer 50, 10785 Berlin, Germany (
Shana S. Warren is a Ph.D. Candidate, New York University, Department of Politics, 19 West 4th Street, 2nd Floor, New York, NY 10012 (
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We are grateful to Eric Arias, Kate Baldwin, Chris Blattman, Dan Butler, Eric Dickson, Pat Egan, Ryan Enos, Don Green, Macartan Humphreys, John Jost, Rebecca Littman, Noam Lupu, Gwyneth McClendon, Jack Snyder, Jonathan Weigel, Rebecca Weitz-Shapiro, and participants in the Contemporary African Political Economy Research Seminar (CAPERS), the NYU Center for Experimental Social Science, and above all to Bernd Beber, for their feedback, advice, and support. Oluwatosin Akinola and Caleb Yanet provided superb leadership in the field. Special thanks go to our dear friend Abel Adejor and to Kyauta Giwa of Community Action for Popular Participation (CAPP), and Chima Nnaedozie and microManna Ltd, our implementing partners. We thank the editor and four anonymous reviewers for helpful comments. The United States Institute of Peace (USIP) and the New York University Research Challenge Fund (URCF) provided funding for this study. This research was approved via NYU IRB Protocol 14-9985. Our pre-analysis plan is available via the Evidence in Governance and Politics (EGAP) Registry, ID 20150617AA. All errors and omissions are our own. Replication files are available on the American Political Science Review Dataverse:

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