Do time of day and developer experience affect commit bugginess?

Abstract

Modern software is often developed over many years with hundreds of thousands of commits. Commit metadata is a rich source of social characteristics, including the commit's time of day and the experience and commit frequency of its author. The "bugginess" of a commit is also a critical property of that commit. In this paper, we investigate the correlation between a commit's social characteristics and its "bugginess"; such results can be very useful for software developers and software engineering researchers. For instance, developers or code reviewers might be well-advised to thoroughly verify commits that are more likely to be buggy.In this paper, we study the correlation between a commit's bugginess and the time of day of the commit, the day of week of the commit, and the experience and commit frequency of the commit authors. We survey two widely-used open source projects: the Linux kernel and PostgreSQL.Our main findings include: (1) commits submitted between midnight and 4 AM (referred to as late-night commits) are significantly buggier and commits between 7 AM and noon are less buggy, implying that developers may want to double-check their own latenight commits; (2) daily-committing developers produce less-buggy commits, indicating that we may want to promote the practice of daily-committing developers reviewing other developers' commits; and (3) the bugginess of commits versus day-of-week varies for different software projects.

Do More Experienced Developers Introduce Fewer Bugs?

“…It is surprising to find that there is no correlation between any of the ways we measure experience and the bug seeding ratio. Our intuition and related research (see Eyolfson et al [2]) had made us expect that developers would increase the quality of their code the more they contribute to a project. However, both results could be compatible.…”

“…From a quantitative point of view, experience has been found to be measured in several ways: a) Number of commits [8,7,2]; b) Fixing activity [1]; and, c) Ownership of the source code [3,4].…”

A Survey on Mining Software Repositories

“…Table 7 presents the detailed category of MSR purposes, their detailed task types, and existing approaches. To support Bug-related activity There have been several studies on bug-fix: empirical study on the patterns for bug-fix [58], [155], automatic bugfix [59], [60], understanding the bug-fix patterns of hardware project [61]. Sliwerski et al conducted the empirical analysis about fix-inducing change based on CVS log and BugZilla [58].…”

“…The number of fix-inducing transactions is about three times that of non-fix inducing transactions. Eyolfson et al studied the co-relationship between the patterns of commits and the bugginess for those commits [155]. They explored the Linux Kernel and Postgres-SQL and found several observations: The commits from midnight to 4 A.M were highly possible to be buggy and the commits of everyday committers were less buggy.…”

Developer Experience Considering Work Difficulty in Software Development*

“…These studies are helpful to understand the main contributor in a specified domain and assign jobs. In addition, previous studies have researched the correlation between developer experience and code quality [2], [3], [5], [7], but the defect tendency of a developer depends on the file complexity. Other works have suggested that experienced developers are more defect-prone because they often work in the most complex regions [5], [7].…”