Long-Term Peer Reviewing Effort is Anti-Reciprocal.

Many studies demonstrate that peer reviewing provides pedagogical benefits such as inspiration and developing expert vision, and changes classroom culture by encouraging reciprocity. However, much large-scale research in peer assessment has focused on MOOCs, where students have short tenures, and is unable to describe how reciprocity-oriented classroom cultures evolve over time. This short paper presents the first long-term analysis of peer reviewing with 304 students, conducted in three large physical classes in a year-long undergraduate series. Surprisingly, this analysis reveals that when students receive better reviews on their work, they write worse reviews in the future. This suggests that while students believe in the reciprocal nature of peer review, they act anti-reciprocally. Therefore, battling the emergent norm of anti-reciprocity is crucial both for system designers and practitioners who use peer assessment.