An empirical study of FOSS developers patterns of contribution: Challenges for data linkage and analysis

The majority of Free and Open Source Software (FOSS) developers are mobile and often use different identities in the projects or communities they participate in. These characteristics pose challenges for researchers studying the presence and contributions of developers across multiple repositories. In this paper, we present a methodology, employ various statistical measures, and leverage Bayesian networks to study the patterns of contribution of 502 developers in both Version Control System (VCS) and mailing list repositories in 20 GNOME projects. Our findings shows that only a small percentage of developers are contributing to both repositories and this cohort is making more commits than they are posting messages to mailing lists. The implications of these findings for understanding the patterns of contribution in FOSS projects and on the quality of the final product are discussed.