Abstract: the information product market, piracy-where products are duplicated by the original manufacturer without the permission or authorization of the copyright owner-invades the market of commercial products, affecting the interests of the monopoly manufacturer. Firstly, we apply the pattern of both the restrictive sale strategy and seeding sale strategy, aiming at this phenomenon, to investigate the selection of sale strategies for information products based on the theory of consumer incentive compatible constraint. Then we establish four models, inclu-ding restrictive sale strategy without piracy model, seeding sale strategy without piracy model, restrictive sale strategy with piracy model and seeding sale strategy with piracy model respectively. Eventually, through compar-atively analyzing the abovefour models, the results show that if there is piracy in the infor mation productmarket, the monopoly manufacturer choosing the restrictive sale strategy will be better than that of choosing the seeding sale strategy. Moreover, when the network externality of information products is very high, without piracy in the information product market, it will be better for the monopoly manufacturer to choose the restrictive sale strategy. As the network externality of information products is moderate, the restrictive sale strategy has no better effect on the interests of the monopoly manufacturer compared to the seeding sale strategy. However, when the network externality of information product is low, which strategy is the better of the two sale strategies will be determined by both the seeding rate of commercial products and the value discount coefficient of the free versions. In addition, by adjusting the prices of commercial products, the strategies can play a significant role in combating piracy, so that the manufacturer would get higher profits.

Key words: information products, piracy, restrictive sale strategy, seeding sale strategy

摘要： 在信息产品市场中存在盗版的情况下,由于盗版产品抢占了正版产品的部分市场,从而导致正版厂商的利益受到损害。本文以消费者激励相容约束理论为依据,基于培育式和限制性的销售策略,针对一个垄断正版厂商销售策略的选择性问题展开了研究,分别建立了无盗版限制性、无盗版培育式和有盗版限制性、有盗版培育式销售策略的四个模型。研究发现,若信息产品市场中存在盗版,正版厂商选择限制性销售策略始终优于选择培育式的销售策略;若信息产品市场中不存在盗版,正版产品的培育率、免费版本的价值折扣系数以及该类信息产品的网络外部性的大小将共同决定选择何种销售策略更优。此外,正版厂商通过调节正版产品的价格能够起到打击盗版产品的作用,从而使其获得较高的收益。

关键词: 信息产品, 盗版, 限制性销售策略, 培育式销售策略