Impact of Peer Code Review on Peer Impression Formation: A Survey

Peer code review has been adopted as an effective quality improvement practice by many Open Source Software (OSS) communities. In addition to increasing software quality, there is anecdotal evidence that peer code review has other benefits, including: sharing knowledge, sharing expertise, sharing development techniques, and most importantly building accurate peer impressions between the code review participants. To further investigate the presence of these benefits, we surveyed members of popular OSS communities who were involved with peer code review. We used established scales from Psychology, Information science, and Organizational Behavior to create survey questions. We also enforced multiple reliability and validity measures to ensure higher confidence in the survey results. In this paper, we present a subset of the surveys results focused on better understanding four aspects of peer impression formation: trust, reliability, perception of expertise, and friendship. The results indicate that there is indeed a high level of trust, reliability, perception of expertise, and friendship between OSS peers who have participated in code review for a period of time. Because code review involves examining someone else's code, unsurprisingly, peer code review helped most in building a perception of expertise between code review partners.