Article
Strategic formation of production networks
We provide a strategic model of the formation of production networks that subsumes the standard
general equilibrium approach. The objective of firms in our setting is to choose their supply
relationships so as to maximize their profit at the general equilibrium that unfolds. We show that
this objective is equivalent to the maximization by the firms of their eigenvector centrality in
the production network. As is common in network formation games based on centrality, there
are multiple Nash equilibria in our setting. We have investigated the characteristics and social
efficiency of these equilibria in a stylized version of our model representing international trade
networks. We show that the impact of network structure on social welfare is firstly determined by
a trade-off between costs of increasing process complexity and positive spillovers on productivity
induced by the diversification of the input mix. We further analyze a variant of our model that
accounts for the risks of disruption of supply relationships. In this setting, we characterize how
social welfare depends on the structure of the production network, the spatial distribution of risks,
and the process of shock aggregation in supply chains. We finally show that simple trade policies
characterized by sets of links that are either prevented or catalyzed can be a powerful equilibrium
selection device.
JEL classification: D85 C65 D83
Keywords: General equilibrium, Network formation, Supply chain, Production networks