Evaluating the Characteristics of Code Reviewers and the Code Reviewed by Them in Open Source Projects

Abstract: Open Source Software (OSS) solutions play an important role in software industry. People all around the world use open source applications in their daily life. Development practices in OSS usually don’t follow established industry standards, teams are often distributed, and experience among team members varies greatly. Nevertheless, OSS has to fulfill the same quality standards as conventional software. Within OSS, gatekeeping is the process of controlling quality in a way that contribution goes through a formal review. OSS use high experienced people (during code reviews) to review and control the commits of less experienced people. But it is not evident, if committers with more experience actually produce higher quality code. In this study we investigate how experience influences the quality of code contributions. This shall enable us to get a better understanding how quality assurance processes in OSS work. This study is carried out to evaluate the characteristics of code reviewers and their contribution efficiency. The study is comprised of six different Apache projects and exploring the facts by using source code characteristics. The results of this study present interesting information about characteristics of code reviewers and contributions made by them. We investigate the relationship between contributor’s experience and contribution efficiency. According to our study results, there is no correlation between contributor’s experience and contribution efficiency. A developer with less experience can also provide efficient contributions. Results of this study can be useful for software professionals, managers and IT researchers.