售后市场中的拒绝交易行为机制研究

Study on the Mechanism of Refusals to Deal in Aftermarkets

自1994年美国柯达公司(Kodak)售后市场反垄断案例开始,售后市场垄断逐渐成为学者关注的热点话题。现有理论阐述了售后市场垄断的成因,却没能解释厂商拒绝向独立维修商出售零配件(拒绝交易)这一行为的经济学动机。论文基于不完全信息和价格歧视理论,探讨厂商通过拒绝交易牟取超额利润的可能性。研究表明:拒绝交易为厂商对售后产品进行歧视性定价提供了保证;双寡头垄断竞争模型下,采取价格歧视的厂商会压低初级产品价格,抢占市场份额从而增加利润;当且仅当双方厂商均采取歧视性定价策略时,博弈存在纳什均衡;在博弈均衡状态,产品的低频使用者(L型消费者)面临更高的产品配件定价,高频使用者(H型消费者)增加了维修产品的学习成本,厂商迫于竞争压低初级产品价格却无法增加利润,这种恶性竞争最终会导致损害效率,导致社会总福利下降。

Since Kodak antitrust case in 1994 happened,monopoly in aftermarket has gradually become a hot topic among scholars.The existing theories have explained the causes of monopoly,but they fail to explain the economic motivation of manufacturers’refusal to sell accessories(refusal to deal)to independent repairers.Based on the theory of incomplete information and price discrimination,this paper discusses the possibility of firms to make excess profits by refusal to deal.It is found that:refusal to deal enables firms to implement discriminatory pricing strategy in aftermarkets;under the duopoly competition model,firms that adopt price discrimination will lower the price of primary products,seize market share and increase profits;if and only if both firms adopt price discrimination,there is a Nash equilibrium in the game.In the equilibrium,low frequency users of primary products(L-type consumers)will face higher prices of accessories,and high frequency users(H-type consumers)will pay the cost of learning maintenance technology,meanwhile the manufacturers are forced to lower the price of primary products and are unable to increase their profits.In the end,the vicious competition will damage efficiency and eventually result in the decline of social welfare.