SVNNAT: Measuring Collaboration in Software Development Networks

We investigate the structures of collaboration in software development groups by analyzing the data derived from the versioning system SVN (subversion) for several open source projects of different types and sizes. The goal of the work presented here is to investigate specific properties of the network topology in the collaboration groups of open source developer communities. For this purpose we developed a software called ´SVN Network Analysis Tool´ (SVNNAT) which helps us to analyze the update data in subversion systems (SVN) with respect to the changes committed to the software code. In order to construct the network topology from the SVN data, we defined a collaboration coefficient that is able to express the strength of the developers´ relationship in terms of their collaboration during the software production process. We present initial results deriving from the application of SVNNAT to several open source projects including up to 871 software developers. After constructing weighted networks from the matrix representation of the collaboration coefficients, we characterize the resulting networks using typical indicators of topology properties like betweenness, closeness, and degree centralization.