The relationship between food production and political stance based on canonical correlation analysis and empirical mode decomposition: taking the U.S.-DPRK relations as an example

The U.S. policy toward North Korea has always been issue of great concern and research focus. According to the grain production data of North Korea, and combined with perspectives from experts of China, the United States and South Korea, this paper tries to make a tentative judgment of the hawk/dove tendency of the five U.S. Presidents' remarks on North Korea from 1989 to 2019. The results show that: (1) The hawkish tendency in the presidents' attitudes has a certain relationship with North Korea's grain production. However, dove tendency is related to grain yield and its fluctuation rate, and the impact of the rate on the dove stance is even greater than the impact of production. (2) When North Korea's grain production increases, the presidents' stance on North Korea's policy tends to be tough; but when its grain production decreases, the presidents' attitudes towards North Korea will become relatively moderate. (3) The fluctuation rate of grain production in North Korea will affect the dove tendency of the presidents. Their stance will be more moderate if the rate decrease. But if the rate rises, the moderation of the statements will retreat.