Welfare gains in the Armington, Krugman and Melitz models: Comparisons grounded on gravity
研究发现，降低全球贸易成本时，梅利茨模型的全球福利收益最大，克鲁格曼模型次之，阿明顿模型最小；劳动休闲选择和中间品是区分结果的关键因素，且垄断竞争模型中的最优关税显著更低。
Abstract Under a wide range of model features, we show that in response to a reduction in global trade costs, the global welfare gains are largest in the Melitz model, followed by the Krugman model, and smallest in Armington. Labor‐leisure choice and intermediate goods are the most important features for differentiating results. We show that the optimal tariff is significantly lower in the monopolistic competition models, thereby moving policy away from protectionism. We are the first to consider multi‐sector comparative‐static welfare impacts of these market structures, while maintaining equal trade responses across the models consistent with a shared structural‐gravity elasticity.