CAN OPINION BE STABLE IN AN OPEN NETWORK WITH HIERARCHY?AN AGENT-BASED MODEL OF THE COMMERCIAL COURT OF PARIS

The co-evolution of social networks and opinion formation has received increasing attention in recent years. As a contribution to the growing literature on this topic, we explore connections between empirical data representing the advice network of judges at the Commercial Court in Paris and an agent-based simulation protocol testing various hypotheses on the motives that drive agent behaviors. A previous work (Rouchier et al. 2007) had already modeled the dynamics of advice-seeking among judges and studied the implications of different rationality assumptions on the shape of the emerging network. Here, we add an influence model to the previously examined advice-seeking relationships in order to explore the possibility that there is a form of “culture” at the Court that harmonizes the opinions of members over time; we identify a set of relevant stylized facts, and we use new indicators to evaluate how agents choose with whom to interact within this framework. The basic assumptions we analyze are that they seek advice from senior judges who are higher up in the hierarchy, who enjoy high reputation, or who are similar to them. Our simulations test which criterion –or which combination of criteria– is most credible, by comparing both the properties of the emerging network and the dynamics of opinion at the Court to the stylized facts. Our results single out the combination of criteria that most likely guide individuals' selection of advisors and provide insight into their effects on opinion formation.