Effort modeling and programmer participation in open source software projects

This paper develops models for programmer participation and effort estimation in open source software projects and employs the results to assess the efficiency of open source software creation. Successful development of such models will be important for decision makers of various kinds. We propose hypotheses based on a prior case study on manpower function and effort modeling. A large data set retrieved from a project repository is used to test these hypotheses. The main results are that if Norden-Rayleigh-based approaches are used, they need to be complemented in order to account for the addition of new features during a product life cycle, and that programmer-participation based effort models result in distinctly lower estimations of effort than those based on output metrics, such as lines of code.