Classmate Peer Effects: Evidence from Core Courses at Three Colleges*

This paper takes advantage of random assignment of first-year students into core-course sections at three liberal-arts colleges to test for classmate peer effects. Our statistical analysis finds no evidence that more able core-course classmates affect students’ mean academic success outside the core course. While there are several possible explanations for this, interviews with core-course instructors suggest that peers’ attitudes and personalities have greater effects than their raw academic abilities. *This paper grew out of an earlier study of classmate peer effects at Reed College, which was undertaken by Jessica Hoel with Parker and Rivenburg under the sponsorship of the Bernard Goldhammer Collaborative Grant Program. The current research is part of a project supported by an Outcomes and Assessments Grant from the Teagle Foundation. Nigel Nicholson, Ruth Russo, Ben Westervelt, Jay Beaman, and Neal Christopherson are members of the Teagle project research team and contributed, directly and indirectly, to this research. The project also benefited from outstanding research assistance over several years from numerous students at all three colleges, including Nick Chandler-Klein, Kathryn Deane, Christa Gibbs, Ranganai Gwati, Joe Hand, Ben Keefer, David Kling, Joshua Lingerfelt, Morgan Matthews, Ramon Mitchell, Daniela Morar, Dylan Smith, Michael Turner, Izarra Varela, and Liza Wickline.