異質雙占廠商的資訊揭露策略與政府規範

Information Disclosure in Differentiated Duopoly Markets

黃千雲(CHIEN-YUN HUANG)

指導教授 ： 謝修

國立臺北大學/社會科學學院/經濟學系/碩士(2016年)

摘要

資訊揭露規範向來都受到各國政府的重視，而資訊在廠商間的競爭確實扮演著重要的角色，若廠商掌握對手產品特性，不僅能清楚彼此的競爭關係，也能適時的調整自己的行銷策略。因此，本論文的目的在於，探討廠商面對產品異質性的資訊不對稱時，基於私利會如何選擇其資訊揭露策略，而政府是否需要透過公權力強制廠商揭露資訊。
　　第一章說明本論文的研究動機與相關文獻回顧，並描繪分析架構與方法。
　　在第二章中，我們考慮的市場架構為私營雙占市場，分別探討在數量競爭及價格競爭下，資訊優勢廠商的最適揭露策略，以及政府的政策方向建議。研究發現，在數量 (價格) 競爭下，當資訊優勢廠商知道雙方產品具有高 (低) 替代性時，揭露資訊為其優勢策略。因此，無論何種競爭模式，均衡時資訊優勢廠商皆無法隱瞞其對手。另一方面，既然均衡時不存在不對稱資訊，則政府也沒有強制廠商揭露資訊之必要。
　　在第三章中，我們考慮的市場架構為混合雙占市場，分別探討在數量競爭及價格競爭下，資訊優勢廠商 (民營廠商) 的最適揭露策略，以及政府的政策方向建議。研究發現，資訊優勢廠商的最適揭露策略不受競爭模式所影響，但均衡時資訊優勢廠商仍然面臨無法隱瞞其對手的情況。因此，政府同樣毋須強制規範廠商揭露資訊，因為即使政府積極介入，也不影響兩廠商的競爭行為與社會福利。
　　最後，我們在第四章總結本論文的研究結果與政策建議。

關鍵字

資訊揭露 ； 異質雙占 ； 混合雙占 ； 異質產品 ； 資訊不對稱 ； 數量競爭 ； 價格競爭

並列摘要

The goal of this thesis is to investigate the optimal disclosure strategy for a duopolistic firm that possesses private information regarding the degree of product differentiation and the appropriate disclosure policy by government under Cournot and Bertrand competition, respectively.
　　Chapter 1 motivates the study, reviews the related literature, and describes the analytical framework as well as the solution concept employed in the thesis.
　　In chapter 2, we consider a private duopoly market in which two firms produce differentiated products, and only one firm has private information about the product heterogeneity. We find that it is a dominant strategy for the firm that possesses private information to disclose information when the goods are close (not close) substitutes under Cournot (Bertrand) competition. Thus, in equilibrium, the firm cannot conceal its private information regardless of the competition mode. The findings imply that mandatory disclosure requirements by government are not necessary.
　　In chapter 3, we consider a mixed duopoly market in which two firms produce differentiated products, and only the private firm has private information about the product heterogeneity. We show that the optimal disclosure strategy does not depend on the competition mode. However, we still obtain the result that the private firm cannot hide its information in equilibrium under both Cournot and Bertrand competition. Thus, a mandatory disclosure requirement by government is an unnecessary policy. This is because even if the government imposes such a requirement, it will not affect the competitive behavior of firms and social welfare.
　　Chapter 4 concludes.

並列關鍵字

disclosure ； differentiated duopoly ； mixed duopoly ； differentiated product ； asymmetric information ； Cournot competition ； Bertrand comprtition

參考文獻

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