During the COVID-19 pandemic, countries applied trade restrictions to insulate their domestic markets from the world market. However, these trade policies could have amplified international market price fluctuations. This paper explores the effects of trade restrictions on international agricultural price volatility. A theoretical model is developed to quantify how trade policies amplify the initial shock. Using panel data covering 71 countries from January 2020 to July 2021, we examine empirically the effects of trade policies on world agricultural price volatility. The results show that trade distortions further induced volatility of world agricultural prices by around 22 percent during the COVID-19 pandemic. The multiplier effects are much more substantial in agricultural exporting countries than in importing countries. Large countries like China and the US could make significant contributions to stabilizing world prices by limiting the extent of unilateral trade policy interventions.

中文翻译：

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COVID-19 大流行期间贸易限制对世界农产品价格波动的影响

在 COVID-19 大流行期间，各国实施贸易限制以将其国内市场与世界市场隔离开来。然而，这些贸易政策可能会放大国际市场价格波动。本文探讨了贸易限制对国际农产品价格波动的影响。开发了一个理论模型来量化贸易政策如何放大最初的冲击。我们使用 2020 年 1 月至 2021 年 7 月涵盖 71 个国家的面板数据，实证检验了贸易政策对世界农产品价格波动的影响。结果表明，在 COVID-19 大流行期间，贸易扭曲进一步导致世界农产品价格波动约 22%。农业出口国的乘数效应比进口国大得多。