双寡头竞争下最优进口贸易政策选择

文章在水平差别产品的伯川德模型中对从量和从价关税进行了分析比较。研究发现，效用函数必须满足一些严格的假设，才能保证征收关税将改善本国社会福利。从量关税的进口限制效果明显强于从价关税。但对于均衡从量关税，总存在一个对能给本国带来更高社会福利的从价关税。两者的差距取决于均衡点本国市场对外国产品的需求弹性，需求弹性越小，社会福利差距越大。

The Choice of Optimal Protection under Oligopoly between Specific Tariff and Ad Valorem Tariff

This paper focuses on the ranking between specific tariff and ad valorem tariff in a Bertrand duopoly models with heterogeneous products.We find that the impact of both kinds of tariffs on domestic welfare depends on the specific characteristics of domestic consumers utility function.Specific tariff is more restrictive than ad valorem tariff on import.For each equilibrium specific tariff,there exists a welfare Pareto-superior ad valorem tariff,and the difference of domestic welfares under these two policy ...