Interaction patterns and efficiency in poly-agent systems

A poly-agent system is a system consisting of agents who take actions for their own interests. This paper takes the sum of agents´ interests as the performance of a poly-agent system and defines efficiency of poly-agent systems from this viewpoint. After formulating necessary concepts like efficiency and interaction pattern for general poly-agent systems, we examine a typical poly-agent system, a duopolistic market. By comparing market efficiencies under three interaction patterns, we show that if increasing production brings about relatively large benefit to consumers, the leader-follower pattern is the most efficient, the noncooperation pattern is the second and the bargaining pattern is the least. Otherwise, bargaining pattern is the most efficient, noncooperation pattern is the second and leader-follower pattern is the least