Clustering and Dependencies in Free/Open Source Software Development: Methodology and Tools
http://www.firstmonday.dk/issues/issue8_4/ghosh/index.html
  peer-reviewed

Aiyer Ghosh, Rishab
First Monday
2003

Abstract:

This paper addresses the problem of measurement of non-monetary economic activity, specifically in the area of free/open source software [1] communities. It describes the problems associated with research on these communities in the absence of measurable monetary transactions, and suggests possible alternatives. A class of techniques using software source code as factual documentation of economic activity is described and a methodology for the extraction, interpretation and analysis of empirical data from software source code is detailed, with the outline of algorithms for identifying collaborative authorship and determining the identity of coherent economic actors in developer communities. Finally, conclusions are drawn from the application of these techniques to a base of software.