Computer-Aided Measurement and Analysis of Food Price Fluctuations Influenced by the Uncertainty of Economic Policy in Big Data Environment

Based on the monthly data of China's grain trade from January 1995 to December 2021, this paper selects four representative grain products of wheat, corn, rice and soybeans, and uses the MS-VAR big data model to analyze the fluctuation status of grain trade. The results show that the four types of grains have a low probability of mutual conversion under the two states of State 1 and State 2, and external factors are the main factors affecting the transition of the two trade states. By measuring the impact of economic policy uncertainty on the four types of grain trade, for corn, wheat and soybean prices, the degree of influence when the degree of uncertainty is higher is greater than when the degree of uncertainty is lower, and for the price of rice, The degree of influence when the degree of uncertainty is high is smaller than when the degree of uncertainty is low, that is, the asymmetry in the degree of influence is increased by 6.7%.