Collaboration between Software Developers and the Impact of Proximity
The research uses ﬁve dimensions of
proximity theory to explore this question:
“How do participants, who are paid by
ﬁrms, collaborate within a ﬂuid
Despite increased participation from paid
software developers, little research has been
conducted to investigate collaboration as it
relates contributors who are employed by
ﬁrms to work within a ﬂuid organization.
Linux Kernel Community Case Study1:
• Open source software
• Over 85% of contributors paid
• Neutral: competing companies
• 19M lines of code
• 11K developers
• 1200 organisations
1. Corbet, J., Kroah-Hartman, G. & McPherson, A., 2015. Linux Kernel Development:
How Fast is it Going, Who is Doing It, What Are They Doing and Who is Sponsoring
the Work, Available at: http://www.linuxfoundation.org/publications/linux-foundation/
2. March, J.G. & Simon, H.A., 1993. Organizations Second Ed., Malden, MA: Blackwell.
3. Dobusch, L. & Schoeneborn, D., 2015. Fluidity, Identity, and Organizationality: The
Communicative Constitution of Anonymous. Journal of Management Studies, 52(8),
4. Glance, N.S. & Huberman, B.A., 1994. Social dilemmas and ﬂuid organizations,
Hillsdale, NJ: Lawrence Erlbaum.
5. Balland, P.A., 2012. Proximity and the Evolution of Collaboration Networks: Evidence
from Research and Development Projects within the Global Navigation Satellite
System (GNSS) Industry. Regional Studies, 46(6), pp.741–756.
6. Crescenzi, R., Nathan, M. & Rodríguez-Pose, A., 2016. Do inventors talk to strangers?
On proximity and collaborative knowledge creation. Research Policy, 45(1), pp.177–
7. Knoben, J. & Oerlemans, L. a G., 2006. Proximity and inter-organizational
collaboration: A literature review. International Journal of Management Reviews, 8(2),
8. Cantner, U. & Graf, H., 2006. The network of innovators in Jena: An application of
social network analysis. Research Policy, 35(4), pp.463–480.
9. Boschma, R., 2005. Proximity and Innovation: A Critical Assessment. Regional
Studies, 39(1), pp. 61–74.
10. Butts, C.T., 2008. A relational event framework for social action. Sociological
Methodology, 38(1), pp.155-200.
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stability in organizational networks: Temporal structures of project teams. Social
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networks: Communication in a Facebook-like community. arXiv preprint arXiv:
Relational Event Framework
• Predicting events in an ordinal sequence is
product of multinomial likelihoods.10
• Ordinal model estimated using Multinomial
Conditional Logistic Regression, speciﬁcally
Cox regression estimated using MLE.11
• Using clogit in R, which is based on coxph.
• Realized event compared to 3 randomly
sampled possible events.12
• 10 day moving window.
March and Simon2 deﬁne organizations as systems for coordinating activities between individuals
to facilitate cooperation with a focus on supporting decision-making processes. The notion of
organization can be expanded to include ﬂuid organizations that emerge when people collaborate
and make decisions within a community that is recognized by its collective identity.3
Collaboration between individuals occurs within these ﬂuid organizations; however, collaboration
within ﬂuid organizations has been shown to reveal complex behavior with many dimensions.4
Proximity theory can been used to investigate various dimensions of collaboration5,6,7 and other
complex topics related to collaboration, such as knowledge transfer and innovation.8,9
There are several approaches to proximity theory7, and this research uses ﬁve dimensions:
cognitive, organizational, social, institutional and geographical.9
Collaboration between Software Developers
and the Impact of Proximity
Dawn M. Foster, Guido Conaldi, Riccardo De Vita
Business School, Centre for Business Network Analysis
• Dataset: USB Mailing List (linux-usb) 2013-11-01 - 2015-11-01
• Messages (Events): 7799 in 3264 threads
• Ties: based on Ego replying to a message from Alter
• Actors: 882 (Egos: 691, Alters: 717)
• Geographic: time zone similarity (temporal geo prox)
• Organizational: both work for same ﬁrm
• Social prox: # of times dyad participated in same thread
• Cognitive prox: contribute to same source code subsystems
• Institutional prox: both employed by ﬁrms
• Is Maintainer: one or both are in leadership (maintainer) position
• Is Committer: one or both have made code contributions
• Alter Maintainer: Alter is in a leadership (maintainer) position
• Transitive closure: num of x’s ego replied to where x has replied to alter
• Cyclic closure: num of x’s alter replied to where x has replied to ego
• Shared partnership in: same x replies to both ego and alter
• Shared partnership out: ego and alter reply to messages by same x
• Repeated events: number of times ego replied to messages by alter
• Recency effect: 1/n with n as number of people alter emailed before ego
• Participation shift: 1 if last person alter replied to on mailing list was ego
XXXVII Sunbelt Conference
30 May 2017 – 4 June 2017
• Proximity is relevant in explaining
collaboration ties within a ﬂuid
• Preliminary results are aligned with
qualitative analysis from interviews
with software developers in this
• Further Research: Expand beyond 2
years of data from one mailing list to
see if the same results hold for other
coef exp(coef) se(coef)
org proximity 5.763e-01 1.779e+00 6.280e-02 ***
social prox 3.369e+01 4.290e+14 1.047e+00 ***
cognitive prox -4.620e-01 6.301e-01 1.237e-01 ***
geo proximity 1.756e-01 1.192e+00 9.354e-02 .
inst prox (corp)2.597e-01 1.297e+00 4.535e-02 ***
is maintainer 5.128e-01 1.670e+00 1.167e-01 ***
is committer 3.335e-01 1.396e+00 5.548e-02 ***
alter maint -6.667e-01 5.134e-01 3.894e-01 .
cyclic closure 1.685e+01 2.080e+07 7.209e-01 ***
shared part in -3.263e+01 6.721e-15 1.020e+00 ***
shared part out-2.713e+01 1.653e-12 1.095e+00 ***
transitive clsr 1.060e+00 2.885e+00 5.555e-01 .
repeated events 1.684e+01 2.051e+07 5.773e-01 ***
recency effect 6.070e+00 4.326e+02 2.362e-01 ***
particip shift -3.090e+00 4.550e-02 2.386e-01 ***
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1