Do We Really Know That the WTO Increases Trade?
用标准引力模型和50多年175国的面板数据，检验GATT/WTO和普惠制对国际贸易的影响，发现加入GATT/WTO并未显著改变贸易模式，但普惠制效果显著。
This paper estimates the effect on international trade of multilateral trade agreements—the World Trade Organization (WTO), its predecessor the General Agreement on Tariffs and Trade (GATT), and the Generalized System of Preferences (GSP) extended from rich countries to developing countries. I use a standard “gravity” model of bilateral merchandise trade and a large panel data set covering over 50 years and 175 countries. An extensive search reveals little evidence that countries joining or belonging to the GATT/WTO have different trade patterns from outsiders, though the GSP seems to have a strong effect.