大國與區域整合集團中貿易自由化程度變化之研究

Regional Great Powers and the Variation of Trade Liberalization between and within Regional Integration Blocks

從二戰結束後至今，全球區域化的發展形成幾個主要的區域整合集團，然而過去的研究和經驗資料卻顯示，雖然各個區域整合集團發展至今都有著自由貿易協定的簽署，但不同集團彼此之間的貿易自由化程度卻有著極大的差距，而且在同一個區域整合集團中，貿易自由化的程度也會隨著時間而有所不同，文獻中關於區域整合或是自由貿易協定的理論，並未能有效解答貿易自由化的程度在「區域內」和「跨區域」的變化。根據「囚徒困境賽局」和「獵鹿賽局」的建議，本文試圖建立一個結構性的理論來解釋這個現象。本文認為，區域中貿易自由化的推動與區域中大國與小國之間的策略互動有關：對於區域中的大國來說，貿易合作就像是「囚徒困境」賽局，此時，若大國的數量愈少，且彼此的利益相似程度愈高，則愈有利於囚徒困境的破解，貿易合作愈容易成功；而對於區域中的小國來說，貿易合作就像是「獵鹿」賽局，當區域中的大國開始合作，則自己最好的策略就是加入合作，以避免受到「貿易轉移」的負面效果，或是被邊緣化失去談判籌碼，反之，當區域中的大國並不積極合作，則自己最好的策略就是持觀望態度，以避免受到「選邊站」的負面影響。在這兩個賽局的邏輯建議之下，本文預期，若該區域整合集團中的大國數量愈少，且這些大國彼此之間的利益相似程度愈高，則該區域整合集團貿易自由化的程度也將愈高，來自全球各個主要區域整合集團從成立以來迄2014年的經驗證據支持了本文的說法。 Since the end of World War II, the process of global regionalization led to the emergence of several regional integration blocks. The literature and empirical evidence have both demonstrated that although countries participating in regional integration blocks sign numerous regional trade agreements or preferential trade agreements, there are salient differences in the degree of trade liberalization across regions, and even within the same region over time. Theories regarding regional integration or preferential trade agreements are not able to offer satisfying explanations to account for why the degree of trade liberalization varies between and within the regional integration blocks. By applying two game-theoretical models — the prisoners' dilemma and the stag-hunt game — I construct a structural argument to account for this phenomenon. I argue that the promotion of regional trade liberalization is strongly related to the strategic interaction between great powers and secondary powers. As for the great powers, their mutual trade cooperation is similar to the prisoners' dilemma scenario. Thus, when the number of great powers in the region is limited and when these great powers have more similar interests, it is easie r for them to solve the dilemma and reach trade cooperation. As for the secondary powers, trade cooperation with other countries in the region is similar to the stag-hunt game scenario, which has two equilibria: if the great powers in the region start to cooperate, the secondary powers tend to actively participate, in order not to suffer from the trade diversion effect or to lose the bargaining power in the future due to being isolated; instead, if the great powers do not cooperate, the secondary powers' best strategy is to wait and see, so they avoid the negative impacts resulting from taking side. Based on these two game-theoretical models, I expect that the degree of trade liberalization in the region will increase with the decrease of “the number of great powers” and their “interest dissimilarity”. Empirical evidence from seven main regional integration blocks across the world confirms my argument.