A NETWORK PERSPECTIVE ON OPEN SOURCE SOFTWARE DEVELOPMENT: TEAM FORMATION AND COMMUNITY PARTICIPATION A Dissertation Submitted to the Faculty of Purdue University by Chen Zhang In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2008 ii ACKNOWLEDGMENTS iii TABLE OF CONTENTS Page LIST OF TABLES.............................................................................................................. v LIST OF FIGURES ........................................................................................................... vi ABSTRACT...................................................................................................................... vii CHAPTER 1. INTRODUCTION ....................................................................................... 1 1.1. Background ................................................................................................................. 1 1.2. Research Questions ...................................................................................................... 4 1.3. Organization ................................................................................................................ 5 CHAPTER 2. EMERGENCE OF NEW PROJECT TEAMS FROM OPEN SOURCE SOFTWARE DEVELOPER NETWORKS: IMPACT OF PRIOR COLLABORATION TIES .................................................................................................................................... 7 2.1. Introduction ................................................................................................................. 7 2.2. Theoretical Development and Hypotheses ................................................................... 11 2.2.1. A Social Network Perspective of Open Source Software Development.................. 11 2.2.2. Perspectives on How Prior Collaborative Ties Affect Project Team Formation ..... 13 2.3. Data and Methods ...................................................................................................... 19 2.3.1. Study Sample .................................................................................................. 19 2.3.2. Measures ......................................................................................................... 21 2.3.3. Analytical Procedures ...................................................................................... 32 2.4. Results ...................................................................................................................... 34 2.4.1. Data Sample and Descriptive Statistics .............................................................. 34 2.4.2. Tests of Hypotheses Predicting Developer Joining Events .................................. 38 2.5. Discussion ................................................................................................................. 42 2.5.1. Summary of Results ......................................................................................... 42 2.5.2. Contribution .................................................................................................... 48 2.5.3. Limitation and Future Research ........................................................................ 49 CHAPTER 3. SHOULD I STAY OR SHOULD I GO: AN EMPIRICAL INVESTIGATION OF MEMBERS’ CONTINUED PARTICIPATION IN OPEN SOURCE PROJECT COMMUNITIES............................................................................ 51 3.1. Introduction ............................................................................................................... 51 3.2. Theoretical Background ............................................................................................. 54 3.2.1. IS Continuance ................................................................................................ 55 3.2.2. Member Participation and Network Externality in Online Communities .............. 56 3.2.3. Organization of Open Source Communities and Member Involvement ................ 60 3.3. Research Model and Hypotheses ................................................................................. 62 3.3.1. Community Benefit Provision ........................................................................... 63 iv 3.3.2. Member Involvement in Innovation Process ...................................................... 66 3.4. Research Methodology ............................................................................................... 72 3.4.1. Data Source ..................................................................................................... 72 3.4.2. Sample ............................................................................................................ 74 3.4.3. Analytical Approach ........................................................................................ 76 3.4.4. Measures ......................................................................................................... 77 3.4.5. Content Analysis of Messages and Responses .................................................... 83 3.5. Analysis and Results .................................................................................................. 87 3.5.1. Descriptive Statistics ........................................................................................ 87 3.5.2. Results of Hypothesis Testing ........................................................................... 88 3.6. Conclusion ................................................................................................................ 93 CHAPTER 4. CONCLUSION.......................................................................................... 98 4.1. Summary .................................................................................................................. 98 4.2. Contributions and Implications ................................................................................... 99 4.3. Future Research ....................................................................................................... 101 LIST OF REFERENCES................................................................................................ 103 Appendices Page Appendix A. Survey of Project Initiators ......................................................................... 115 Appendix B. Robustness Checks for Essay 1 .................................................................... 118 Appendix C. Coding Scheme for Message Content Analysis in Essay 2 ............................. 127 Appendix D. Robustness Check for Essay 2 ..................................................................... 131 v LIST OF TABLES Table Page Table 2.1 Composite Measures of Outcome and Strength of Prior Collaborative Ties with Project Members ............................................................................................... 24 Table 2.2 Summary of Measures ...................................................................................... 31 Table 2.3 Domain Distribution of Sample Projects.......................................................... 35 Table 2.4 Descriptive Statistics......................................................................................... 35 Table 2.5 Inter-Correlations.............................................................................................. 37 Table 2.6 Logistic Regression Results.............................................................................. 39 Table 3.1 Activities Associated with Levels of Member Involvement in OSSD............. 68 Table 3.2 Distribution of Forum Activity Volume ........................................................... 75 Table 3.3 Distribution of Sample Projects Based on Topics ............................................ 76 Table 3.4 Distribution of Sample Thread-Initiating Messages Based on Member Involvement ...................................................................................................... 85 Table 3.5 Descriptive Statistics......................................................................................... 87 Table 3.6 Pairwise Correlations........................................................................................ 88 Table 3.7 Results of Logistic Regression on Community Response (H1a, H1b, H3a and H3b) .................................................................................................................. 90 Table 3.8 Results of Cox Proportional Hazards Model on Repeated Participation (H2, H4a and H4b).................................................................................................... 92 Appendix Table Page Table A.1 Descriptive Statistics – Projects Associated with Survey Respondents vs. Sample Projects in Essay 1 ............................................................................ 117 Table B.1 Maximum and Minimum Used as Aggregate Measures to Compute Tie Measures Between Developers and Non-Initiator Members ......................... 118 Table B.2 ActivityPercentile as a Continuous Variable.................................................. 119 Table B.3 All Developers at SourceForge ...................................................................... 120 Table B.4 Recent Matching Scores................................................................................. 121 Table B.5 Full Sample vs. Sub-Sample (Projects with at Least One Joiner).................. 122 Table B.6 Domain Distribution of Sample Projects and Projects with Joiners .............. 123 Table B.7 Domain Dummies Used Instead of DomainPopularity