Self-Enforcing Trade Agreements: Evidence from Time-Varying Trade Policy
研究了Bagwell和Staiger（1990）的合作贸易协定理论，发现1997-2006年间美国进口政策与理论预测一致：新关税随进口增长和弹性倒数增加，随进口波动性降低。
The Bagwell and Staiger (1990) theory of cooperative trade agreements predicts new tariffs (i) increase with imports, (ii) increase with the inverse of the sum of the import demand and export supply elasticities, and (iii) decrease with the variance of imports. We find US import policy during 1997–2006 to be consistent with this theory. A one standard deviation increase in import growth, the inverse of the sum of the import demand and export supply elasticity, and the standard deviation of import growth changes the probability that the US imposes an antidumping tariff by 35 percent, by 88 percent, and by –76 percent, respectively.