PREFERENTIAL TRADE AGREEMENTS AND MULTILATERAL TARIFF COOPERATION*
在一个无限重复关税博弈中研究优惠贸易协定（PTA）对多边贸易自由化的影响，发现对称国家中自由贸易协定和关税同盟会破坏多边合作，但在非对称条件下PTA可能促进合作。
Are preferential trade agreements (PTAs) building or stumbling blocks for multilateral trade liberalization? I address this question in an infinitely repeated tariff game between three countries engaged in intraindustry trade under oligopoly. The central result is that when countries are symmetric, a free trade agreement (FTA) undermines multilateral tariff cooperation by adversely affecting the cooperation incentive of the nonmember whereas a customs union (CU) does so via its effect on the cooperation incentives of members. However, when countries are asymmetric with respect to either market size or cost, there exist circumstances where PTAs facilitate multilateral tariff cooperation.