中文摘要：

针对文献孤立地研究网络外部性或市场进入柔性对市场进入决策的影响这一缺陷，从消费者的效用出发，推导出市场需求曲线，进而在事后古诺竞争的规则下研究了网络外部性、市场进入柔性以及二者共同对市场进入决策的影响和网络外部性对市场进入机会的价值的影响．结果表明，在市场演进服从几何布朗运动和古诺竞争的假定下，网络外部性促进市场进入并增加市场进入机会的价值，而市场进入柔性会延迟市场进入，因此观察到的市场进入是网络外部性与市场进入柔性之间力量对比的结果．

英文摘要：

Focusing on the ignorance of co-impacts of network externality and flexible decision on market-entry, this paper derives the demand curve from consumers＇ utilities in the market with network externality, and then, under Cournot competition, examines the sole impacts of network externality or flexible decision and their co-impacts on market-entry decision. Based on these, this paper also studies the effects of network externality on the value of a flexible market-entry opportunity. The results show that under the assumption of geometric Brown motion market and ex post Cournot competition, network externality advances market-entry and raises the value of a flexible market-entry opportunity while market-entry flexibility puts off such an entry. This implies that an observed entry is the outcome of the balancing between the force of network extemality and that of flexibility to a market-entry decision.