Developer participation is the main drive force of software development process especially for open source software systems. Since the open source software development process is partly participated by peripheral developers whose participation is not always guarantee, maintaining and managing their participation can be challenging. Indeed, lacking developer participation where and when it is needed can impact software quality and health.
This thesis performs three empirical studies and a practitioner survey in order to better understand how software development teams can improve the participation practices and thus to ensure software quality and health. This thesis first performs two studies to investigate the impact of developer turnover and code review on software quality. I observe that (1) in addition to technical factors, developer turnover can be associated to software quality in some development cycles, and (2) there is the lack of reviewer participation in code review process.
This thesis then performs another study and a practitioner survey to investigate reviewer participation and how to mitigate the lack of reviewer participation in code review process. I observe that (1) human factors play an important role in influencing the participation decision of reviewers, and (2) only the minority of practitioners are aware of the importance of human factors.
The results and observations highlight the need for better understanding about the human factors which are associate with developer participation, thus leading to a better developer participation, software quality and software health.