  Understanding online communities requires an appreciation of both structure
and culture. But basic questions remain difficult to pose. How do these facets
interact and drive each other? Using data on the membership and governance
styles of 5,000 small-scale online communities, we construct empirical measures
for cross-server similarities in institutional structure and culture to explore
the influence of institutional environment on their culture, and the influence
of culture on their institutional environment. To establish the influence of
culture and institutions on each other, we construct networks of communities,
linking those that are more similar either in their members or governance. We
then use network analysis to assess the causal relationships between shared
culture and institutions. Our result shows that while effects in both
directions are evident, there is a much stronger role for institutions on
culture than culture on institutions. These processes are evident within
administrative and informational type rules.
