The Trade-Comovement Puzzle
标准理论预测贸易与商业周期同步性关联弱，形成贸易同步之谜。本文分析三种可能解释：金融市场摩擦、GHH偏好、短期低长期高的动态贸易弹性，发现第三种最有效。
Standard international transmission mechanism of productivity shocks predicts a weak endogenous linkage between trade and business cycle synchronization: a problem known as the trade-comovement puzzle. We provide the foundational analysis of the puzzle, pointing to three natural candidate resolutions: (i) financial market frictions, (ii) Greenwood-Hercowitz-Huffman preferences, and (iii) dynamic trade elasticity that is low in the short run but high in the long run. We show the effects of each of these candidate resolutions analytically and evaluate them quantitatively. We find that while (i) and (ii) fall short of the data, (iii) goes a long way toward resolving the puzzle.