本論文建立一個兩國兩廠商的模型，進口國存在生產高品質的廠商，出口國則是生產低品質的廠商。本文探討兩國廠商在高品質國家做Cournot競爭或相互合作的情況下，兩國政府選擇政策時間點對廠商利潤和社會福利的影響，而為使自身國內的社會福利最大，政府的政策究竟是會實施補貼或課稅政策? 
    利用二階段賽局，令政府決定完政策後，廠商再做Cournot競爭或相互合作。政府政策時間點的表現，採用同時決定政策或是Stckelberg的模型。
    本文發現，當廠商進行Cournot數量競爭時，生產高品質產品的進口國政府後決定政策，對高品質的進口國及低品質的出口國，不管是廠商的利潤或是兩國的社會福利都是最好的。當廠商相互合作時，以廠商利潤來看，兩國廠商皆會偏好自己國家政府後做政策決定為最好。以國家社會福利來看，生產高品質的進口國先做決定對兩國的社會福利都是最好的。

This paper sets up a trade model with two countries in the world market. Each country has a monopolistic firm. They produce quality-different product. Assume that the product produced by the firm in the import country has higher quality than the product produced in the export country. We explore the impact of the timing of government’s policy making on two firms’ profits and two countries’ social welfare under two firms doing Cournot competition and collusion. Also, to maximize social welfare, the government should apply subsidy or tax on their domestic firm?
Using two stage game, after the government decides the policy, the firms do Cournot competition or collusion in the market of import country. The timing of the government policy-making can be expressed by Stackelberg’s leader-follower model and Cournot conjectural variation assumption. 
This article finds that when firms are doing Cournot competition, the import country with high quality product behaves as a follower would be the best outcome for either profits of two firms or social welfare of two countries. However, when the firms colluding with each other, both firms would like to have a second mover government to have more profit, but both government would like to be a first mover to maximize its own country’s social welfare.

第一章  緒論………………………………………………………………………………………………..1
第一節  研究動機與目的………………………………………………………………………1
第二節  研究方法與架構………………………………………………………………………2
第二章  文獻回顧………………………………………………………………………………………..4
第三章  模型建立………………………………………………………………………………………..8
第四章  兩國廠商進行Cournot競爭………………………………………………………..11
第一節  廠商進行Cournot競爭………………………………………………………….11
第二節  兩國政府決定政策…………………………………………………………………15
第三節  小結………………………………………………………………………………………..38
第五章  兩國廠商彼此相互合作……………………………………………………………….....40
第一節  兩廠商彼此相互合作……………………………………………………………..40
第二節  兩國政府決定政策…………………………………………………………………44
第三節  小結………………………………………………………………………………………64
第六章  結論………………………………………………………………………………………………67
參考文獻………………………………………………………………………………………………………68

參考文獻

一、	中文部分

1.	鍾暳陵 『不同市場結構之垂直整合與最適品質』，博士論文，國立東華大學經濟系。
2.	趙重諺(1995) 『垂直相關市場之產品品質與最適貿易政策』，碩士論文，國立東華大學國際經濟研究所。
二、	英文部分

1.	Anderson, Simon P. and Maxim Engers (1991) “Stackelberg Versus Cournot Oligopoly Equilibrium” International Journal of Industrial Organization 10 (1992) 127-135.
2.	Bond, W. Eric (1988) “Optimal Commercial Policy with Quality-differentiated Products” Journal of International Economics, 25, 271-290.
3.	Cooper, Russell and Raymond Riezman (1989) “Uncertainty and the Choice of Trade Policy in Oligopolistic Industries” Review of Economic Studies 56, 129-140.
4.	Collie, David (1991) “Export Subsidies and Countervailing tariffs” Journal of International Economics 31,309-324.
5.	Haan, Marco  and Hans Maks (1996) “Stackelberg and Cournot Competition under Equilibrium Limit Pricing” Journal of Economic Studies, Vol. 23 Iss: 5/6, 110 – 127.
6.	Huck, Steffen Wieland Muller and Hans-Theo Normann (2001) “Stackelberg Beats Cournot: On Collusion and Efficiency in Experimental Markets” The Economic Journal, 111 (October), 749-765.
7.	Hayashibara, Masayuki (2002) “Industrial Concentration Reverses the Timing in a Trade Game” Open Economies ReviewJanuary , Volume 13, Issue 1, 73-86.
8.	Hwang, Hong、Chao-Cheng Mai and Hiroshi Ohta (2010) “Export Subsidies, Cost Differential and Product Quality” Pacific Economic Review, 15: 1.
9.	Julien, A. Ludovic (2011) “ A Note on Stackelberg Competition”  Journal of Economics , Volume 103, Issue 2,  171-187.
10.	Matsumura, Toshihiro and Daisuke Shimizu (2005) “Cournot and Bertrand in Shipping Models with Circular markets” Journal compilation 2006, Issue 4 (November), 585-598.
11.	Neary, J. Peter (1994) “Cost Asymmetries in International Subsidy Games: Should Governments Help Winners or Losers?” Journal of International Economics, 37, 197-218.
12.	Ries, C. John (1993) “Voluntary Export Restraints, Profits, and Quality Adjustment” The Canadian Journal of Economics / Revue canadienne d'Economique, Vol. 26, No. 3, 688-706.
13.	Spencer, J. Barbara , Dongsheng Zhou and Ilan Vertinsky (2001) “Strategic Trade Policy with Endogenous Choice of Quality and Asymmetric Costs” Journal of International Economics, 56, 205–232.
14.	Toshimitsu, Tsuyoshi (2012) “A Note on the Endogenous Timing of Tariff Policy in the Presence of a Time Lag between Production and Trade Decisions” Open Econ Rev (2013) 24:361–369.
15.	Yuan, Lasheng (2001) “Divisionalisation and Cournot Competition Yield Bertrand Outcomes” Australian Economic ,Volume 40, Issue 1,  22–29.