Journal of International Economics · 2026 · Pawel Michal Krolikowski、Andrew H. McCallum
中文摘要
我们在一个一般均衡动态模型中研究关税,该模型刻画了异质性出口生产商与进口零售商之间的搜寻摩擦。我们证明该模型存在唯一均衡,并在外国被动反应的情形下,解析刻画了使福利最大化的本国单边进口关税。搜寻摩擦在标准最优关税表达式中增加了两项:一项在接触率较低时降低关税;另一项在私人出口成本超过社会机会成本时降低关税。搜寻摩擦还因市场厚度效应而引入了补贴进口的新激励。我们将基准模型校准至美国和中国的2016年数据,并将其与一个反事实情形进行比较:该情形将国际搜寻成本降至国内水平,但所有其他参数保持不变。我们发现,较高的基准搜寻成本会降低美国最优单边关税与纳什关税,并减弱福利对关税变化的反应。
Abstract
We study tariffs in a general equilibrium dynamic model with search frictions between heterogeneous exporting producers and importing retailers. We show the model has a unique equilibrium and analytically characterize home unilateral import tariffs that maximize welfare given a passive foreign country. Search frictions add two terms to the standard optimal tariff expression: One lowers tariffs when contact rates are low; another when private export costs exceed social opportunity costs. Search frictions also introduce new incentives to subsidize imports due to market thickness effects. We calibrate our baseline to U.S. and Chinese 2016 data. We compare this baseline to a counterfactual with international search costs reduced to domestic levels but with all other parameters fixed. We find that higher baseline search costs reduce optimal U.S. unilateral and Nash tariffs and attenuate welfare responses to tariff changes.