AN EXPLORATORY STUDY OF FACTORS INFLUENCING THE LEVEL OF VITALITY AND POPULARITY OF OPEN SOURCE PROJECTS

In this research, we ask the question: What differentiates successful from unsuccessful open source software projects? Using a sample of 240 open source projects, we examine how organizational sponsorship, target audience (developer versus end user), license choice, and development status interact over time to influence the extent to which open source software projects attract user attention and developer activity. 1 RESEARCH OBJECTIVES AND QUESTIONS There is growing interest in open source software (OSS) development in industry, government, and academia. OSS development is different from traditional software development in that it depends on volunteer labor pools coordinating their effort without a common organizational superstructure, and the end product is generally provided freely (Feller and Fitzgerald 2002). There are many ways to define success in the context of OSS development. Market penetration is often cited when discussing well-known open source software, such as Linux and Apache. A similar indicator for less well-known projects might be the number of subscribers to the projecti.e., the number of people who monitor announcements and new releases is one indicator of public interest. Another metric of interest is the number of people who contribute to a project, a figure that may be hard to determine, as evidenced by the widely varying numbers reported for Linux, ranging from about 1,200 (McConnell 1999) to hundreds of thousands (Torvalds and Diamond 2001). The output of those contributors (e.g., in terms of new software releases) is also a potential indicator of success. As is evident from Feller and Fitzgeralds (2002) discussion, there is an accumulated body of common wisdom about what makes OSS development successful, but there is also a need for rigorous research and empirical examination of the phenomenon to confirm or refute this common wisdom. Our goal in this study is to provide an initial empirical investigation into factors that influence project success. Are some kinds of projects more successful than others? We analyze projects listed on the www.freshmeat. net developer forum, and we operationalize success in terms of two indicators available on that forum. These are the vitality on the project, an indicator of how much developer effort and attention is expended on it, and the popularity of the project, an indicator of how much user attention is focused on it. Given that these metrics are tracked within the OSS community, we believe they are of practical relevance. Vitality is calculated using the number of announcements about a project and the time since its last release. Popularity is based on the number of people who subscribe to the project as well as hits to the Website. We hope the study will contribute to the research literature by helping to develop an initial understanding of the context of open source development and factors that may distinguish it from more traditional development. Some have argued that the organizational processes employed in open source development are typical of virtual organizations and may be applicable in other Stewart & Ammeter/Vitality and Popularity of Open Source Projects FUDfear, uncertainty, doubtis an abbreviation used in a Microsoft memorandum describing ways that users may be discouraged from adopting non-Microsoft products. See www.opensource. org for a detailed description of the licensing requirements. 2 2002  Twenty-Third International Conference on Information Systems domains (e.g., Gallivan 2001; Markus et al. 2000). Hence, increasing our understanding of what leads to success in OSS may help to increase our understanding of other kinds of virtual organizations.