Succession: Measuring transfer of code and developer productivity

Code ownership transfer or succession is a crucial ingredient in open source code reuse and in offshoring projects. Measuring succession can help understand factors that affect the success of such transfers and suggest ways to make them more efficient. We propose and evaluate several methods to measure succession based on the chronology and traces of developer activities. Using ten instances of offshoring succession identified through interviews, we find that the best succession measure can accurately pinpoint the most likely mentors. We model the productivity ratio of more than 1000 developer pairs involved in the succession to test conjectures formulated using the organizational socialization theory and find the ratio to decrease for instances of offshoring and for mentors who have worked primarily on a single project or have transferred ownership for their non-primary project code, thus supporting a theory-based conjectures and providing practical suggestions on how to improve succession.