Given the importance of the U.S. in global commodity markets, the goal is to explore whether U.S. economic policy uncertainty impacts the price performance of certain commodities. The analysis uses the Granger causality in quantiles method that allows us to test whether there are different effects under different market conditions. The results document that economic uncertainty impacts the returns on the commodities considered, with the effects clustering around the tail of their conditional distribution. Robust evidence was obtained under alternative definitions of uncertainty.

中文翻译：

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基于分位数中格兰杰因果关系的商品市场的周期性与美国经济政策不确定性的关系

鉴于美国在全球大宗商品市场中的重要性，目标是探索美国经济政策的不确定性是否会影响某些商品的价格表现。分析使用分位数的格兰杰因果关系方法，该方法使我们能够检验在不同的市场条件下是否存在不同的影响。结果表明，经济不确定性影响所考虑商品的收益，其影响集中在其有条件分配的尾部。在不确定性的替代定义下获得了有力的证据。