The tariff may be nationally optimal, but It 'still means a net loss to the world.

关税对国家也许是最适当的，但对世界来说则仍然意味着净损失。

youdao

Suppose there is no imitation, license contract with two-part tariff or pure royalty per unit may be the optimal licensing strategy in product-differentiated Cournot Duopoly.

假设不存在模仿的可能性，发现在古诺异质产品市场中，两部制许可方式和单一的提成许可方式都有可能成为最优的许可权策略。

youdao

Finally, I will admit that there is something called optimal tariff theory.

FORBES: Three responses to Noahpinion