本文與相關文獻作為對照，旨在探討混和寡占市場下民營企業進行勾結的誘因，並分析廠商在數量競爭以及價格競爭下卡特爾集團的穩定性。我們透過剖析不同競爭模式下產量、價格、廠商利潤、消費者剩餘及社會福利等變量的變動情形，得到在混和寡占市場下廠商進行價格競爭相較於數量競爭更有利於民營企業之間的勾結。若與傳統的純粹寡占模型進行比較，本論文的研究成果也顯示，當寡占市場進行數量競爭時，公營事業的存在會讓民營企業之間的勾結行為不容易成功。

This paper compares relevant papers from these years. We use the public sector in a pure oligopoly market to figure out the incentives for private enterprises to choose to collude in a mixed oligopoly market and analyze the changes in the Cartel group’s stability between many variables such as total production, price, profit, consumer surplus, and social welfare under two models of quantity competition and price competition at the same time. In the end, the result proves among manufacturers in a mixed-oligopoly market under price competition are more conducive to collusion among private enterprises than quantity competition. If we compared the result with the traditional pure oligopoly model, our research result also shows that when the oligopoly market conducts a quantitative competition, the existence of public enterprises will make the collusion of private enterprises difficult.

論文審定書 i
摘要 ii
Abstract iii
目錄 iv
表次 v
第一章 前言 1
第二章 模型設定 5
第三章 Cournot 競爭 8
第一節 沒有卡特爾組織下的市場均衡 8
第二節 成立卡特爾組織下的市場均衡 9
第三節 勾結的穩定性 11
第四章 Bertrand 競爭 14
第一節 沒有卡特爾組織下的市場均衡 14
第二節 成立卡特爾組織下的市場均衡 15
第三節 勾結的穩定性 17
第五章 模型比較 20
第六章 結論 22
參考文獻 23
附錄 26

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