Abstract: Recently, copycat has attracted a great social attention. In this paper, we construct a two-period game model between a brand manufacturer and a copycat, where customers are strategic. The manufacturer acts the market monopolist in the first period, while if the copycat enters the market at the beginning of the second period, it will become a duopoly market. Except for the competition effects caused by the entry of copycat, the similar design of the two products will also cause network effects, thereby increasing the market acceptance of the branded product. Thus, faced with the potential entry of the copycat, the manufacturer should balance the trade-off between negative competition effects and positive network effects at the same time. Our results show that: (1)network effects may not always have positive effects on the price and demand of the manufacturer and the copycat. (2)the quality of the copycat’s products cannot be over-improved. When the quality of copycat’s product is sufficiently close to that of the manufacturer, both two firms may be worse off. (3)when the network effects is higher or the quality of copycat’s product is lower, the brand manufacturer’s demand under monopoly market may be lower than that under the duopoly market.

Key words: network effects, copycat, strategic customers, entry-deterrence strategy

摘要： 近年来,品牌商与模仿者的竞争问题引起了社会的广泛关注。本文构建了包含一个品牌商和一个潜在模仿者的两周期动态博弈模型,且消费者具有策略性行为。品牌商在第一周期是市场的垄断者,若模仿者在第二周期进入市场,那么第二周期会变成双寡头市场。模仿者入侵市场除了会引起竞争效应外,与品牌产品的相似性也会引起网络效应,从而增加品牌产品的市场接受度。因此,面对模仿者入侵,品牌商需要同时权衡竞争效应与网络效应两方面的影响。研究结果表明:(1)网络效应并不总是对品牌商和模仿者的价格和需求等产生积极影响。(2)模仿产品质量不可提升过高,当模仿产品质量和品牌产品质量过分接近时,两个企业的利润都会降低。(3)当网络效应较小或者模仿产品质量过高时,品牌商在双寡头市场的需求可能会高于垄断市场的需求。

关键词: 网络效应, 模仿者, 策略型消费者, 抵御策略