在行銷學和經濟學的領域中，企業如何面對競爭者進入的反應長久以來是一個受到重視的議題。一個原本屬於獨占的市場，經常因為具有超額利潤而可能招致新進入者來加入市場與之競爭、瓜分市場。在一般大眾的印象、想法中，多認為：市場中的先進廠商（Incumbent firm）為了確保自身的市場佔有率及利益，必會針對此進入者（New entrant）做出強烈的反擊來恫嚇、示威。但事實上在這種從獨占到競爭的過程中，情況卻不是想大家所推測那般簡單，先進廠商並不一定會馬上對新做出反擊策略，他並不是只有這唯一一條路而已，他可能可以採取遞延、延遲反擊、或配合的策略，利益或許還比直接反擊更佳。在1998年，Ajay Kalra, Surendra Rajiv和 Kannan Srinivasan就曾對此議題做了很詳細的研究，且建立了一個完整的邏輯模型來說明，原有廠商的延遲回應確實是一項理性的策略。但是我們發現這模型似乎沒有很完整，並不符合Nash均衡的概念，在作者宣稱的均衡下，仍有廠商存在偏離的誘因。因此本研究希望提供一個更完整、正確的邏輯思考模型來修正原作者提出的混合均衡，提出一個穩定的均衡，以解釋延遲反應此現象的合理性。證明當市場存在訊息不對稱，廠商相較於消費者擁有較多訊息時，先進廠商的確不必對新進者採取馬上的完全訊息下的降價反應，而可以延遲降價的必要性。在正文中我們將更正確的證明市場先進廠商的遞延、延遲反應確實是一種理性下的策略選擇。

Competitive reaction to entry is an important issue in the marketing and economics areas. The monopolistic incumbent of a market often faces competitive entry if the market is profitable. This is a common issue that often occurs in the market transition from monopoly to competition. The entrant not only enters the market, but also wants to signal to tell consumers his quality level. The incumbent's reaction is also a signal to the consumers. Thus, how should the incumbent do? The paper "Response to Competitive Entry: A Rationale for Delayed Defensive Reaction" which is written by Ajay Kalra, Surendra Rajiv and Kannan Srinivasan (1998) and published in Marketing Science provides a completed and clear explanation of this issue. They claim that the incumbent would delay the defensive reaction to the competitive entry under information asymmetry. But it is still incorrect. Hence, we want to provide a revision to support that delayed defensive reaction is really a rational response to competitive entry, and explain this issue correctly and logically. We analyze the strategic interactions of the incumbent and the entrants which were omitted previously. Finally, we would obtain the conclusion that is also supporting this point of view： delayed defensive reaction is really a rational response to competitive. And it is really a Nash equilibrium, no firms would deviate.

第一章、序論...............................................7
第二章、簡介“Response to Competitive Entry： A Rationale for Delayed Defensive Reaction”......10
第一節 消費者模型................................................11
第二節 分析......................................................13
第三章、評論與補救........................................18
第四章、結論..............................................22
參考文獻.................................................23
附錄.....................................................24

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