Market Sharing Agreements and Collusive Networks*
分析寡头市场与采购拍卖中企业互不进入对方市场的协议，这些协议构成合谋网络。研究发现对称情形下稳定网络由大于最小规模的完全联盟组成，且协议数量介于行业最优与社会最优之间。
We analyze reciprocal market sharing agreements by which firms commit not to enter each other's territory in oligopolistic markets and procurement auctions. The set of market sharing agreements defines a collusive network. We characterize stable collusive networks when firms and markets are symmetric. Stable networks are formed of complete alliances, of different sizes, larger than a minimal threshold. Typically, stable networks display fewer agreements than the optimal network for the industry and more agreements than the socially optimal network. When firms or markets are asymmetric, stable networks may involve incomplete alliances and be underconnected with respect to the social optimum.