Welfare with the maximum‐revenue tariff is compared to free‐trade welfare under Cournot duopoly with differentiated products; under Bertrand duopoly with differentiated products; and under perfect competition in the case of a large country able to affect its terms of trade. Under Cournot duopoly and Bertrand duopoly, assuming linear demands and constant marginal costs, welfare with the maximum‐revenue tariff is always higher than free‐trade welfare. Under perfect competition, assuming linear demand and supply, welfare with the maximum‐revenue tariff will be higher than free‐trade welfare if the country has sufficient market power.

中文翻译：

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最高收入关税与自由贸易

将最高收入关税福利与古诺双头垄断下差异产品的自由贸易福利进行比较；在 Bertrand 双头垄断下，产品差异化；在完全竞争的情况下，大国能够影响其贸易条件。在古诺双头垄断和伯特兰双头垄断下，假设线性需求和恒定边际成本，最大收入关税的福利总是高于自由贸易福利。在完全竞争条件下，假设供需呈线性关系，如果国家有足够的市场支配力，最高收入关税的福利将高于自由贸易的福利。