Flat for the few, steep for the many: Structural cohesion as a measure of hierarchy in FLOSS communities

A discrepancy exists between the emphasis posed by practitioners on decentralized and non-hierarchical communication in Free/Libre Open Source Software (FLOSS) communities and empirical evidence of their hierarchical structure. In order to explain this apparent paradox it is here hypothesized that in FLOSS communities local sub-groups exist and are less hierarchical, more decentralized than the whole social network to which they belong. A measure of structural cohesion based on network node connectivity is proposed as an effective method to test whether FLOSS communication networks can be decomposed in nested hierarchies of progressively less centralized sub-groups. Preliminary results from a case study that are consistent with the hypothesis are presented and discussed.