Tariffs, Trade and Productivity: A Quantitative Evaluation of Heterogeneous Firm Models
利用1989年美加自由贸易协定数据，检验异质性企业模型对贸易流量和生产率增长的预测能力，发现多数模型低估了生产率增长，而多产品企业扩展模型能更好拟合现实。
We examine the quantitative predictions of heterogeneous firm in the context of the Canada–US Free Trade Agreement (CUSFTA) of 1989. We compute predicted increases in trade flows and measured productivity and compare them to the post-CUSFTA increases observed in the data. Most models predict increases in measured productivity that are too low by an order of magnitude relative to predicted increases in trade flows. A multi-product firm extension that allows for within-firm productivity increases has the potential to reconcile model predictions with the data.