@proceedings {Wiggins:2009,
	title = {Heartbeat: Measuring Active User Base and Potential User Interest in FLOSS Projects},
	volume = {299},
	year = {2009},
	pages = {94-104},
	publisher = {Springer Boston},
	address = {Skövde, Sweden, 3-6 June},
	abstract = {This paper presents a novel method and algorithm to measure the size of an open source project{\textquoteright}s user base and the level of potential user interest that it generates. Previously unavailable download data at a daily resolution confirms hypothesized patterns related to release cycles. In short, regular users rapidly download the software after a new release giving a way to measure the active user base. In contrast, potential new users download the application independently of the release cycle, and the daily download figures tend to plateau at this rate when a release has not been made for some time. An algorithm for estimating these measures from download time series is demonstrated and the measures are examined over time in two open source projects.},
	isbn = {978-3-642-02031-5},
	issn = {978-3-642-02031-5},
	doi = {10.1007/978-3-642-02032-2\%5f10},
	attachments = {https://floss.syr.edu/sites/crowston.syr.edu/files/heartbeat.pdf},
	author = {Wiggins, Andrea and James Howison and Kevin Crowston},
	editor = {Boldyreff, Cornelia and Kevin Crowston and Lundell, Bj{\"o}rn and Wasserman, Tony}
}
@article {Crowston:2006a,
	title = {Hierarchy and centralization in Free and Open Source Software team communications},
	journal = {Knowledge, Technology \& Policy},
	volume = {18},
	number = {4},
	year = {2006},
	pages = {65{\textendash}85},
	abstract = {Free/Libre Open Source Software (FLOSS) development teams provide an interesting and convenient setting for studying distributed work. We begin by answering perhaps the most basic question: what is the social structure of these teams? Based on a social network analysis of interactions represented in 62,110 bug reports from 122 large and active projects, we find that some OSS teams are highly centralized, but contrary to expectation, others are not. Projects are mostly quite hierarchical on four measures of hierarchy, consistent with past research but contrary to the popular image of these projects. Furthermore, we find that the level of centralization is negatively correlated with project size, suggesting that larger projects become more modular. The paper makes a further methodological contribution by identifying appropriate analysis approaches for interaction data. We conclude by sketching directions for future research.},
	keywords = {FLOSS},
	attachments = {https://floss.syr.edu/sites/crowston.syr.edu/files/HierarchyAndCentralization.pdf},
	author = {Kevin Crowston and James Howison}
}
