Explaining the structure of inter-organizational networks using exponential random graph models: does proximity matter?

A key question raised in recent years is which factors determine the structure of inter-organizational networks. While the focus has primarily been on different forms of proximity between organizations, which are determinants at the dyad level, recently determinants at the node and structural level have been highlighted as well. To identify the relative importance of determinants at these three different levels for the structure of networks that are observable at only one point in time, we propose the use of exponential random graph models. Their usefulness is exemplified by an analysis of the structure of the knowledge network in the Dutch aviation industry in 2008 for which we find determinants at all different levels to matter. Out of different forms of proximity, we find that once we control for determinants at the node and structural network level, only social proximity remains significant.