Frequency Domain"Ripple Effect"in Commodity Futures Markets:A Bidirectional"Ripple"Index Method from a Hedging Perspective
Accurately identifying network spillovers and"ripple effects"in commodity futures markets is crucial for mitigating systemic risks in financial markets.In light of this,a bidirectional"ripple"index test method based on a hedging perspective is proposed.Utilizing 5-minute high-frequency data and wavelet packet decomposition,this study examined the bidirectional"ripple effects"in commodity futures markets from a frequency domain perspective.The study revealed that,during the sample period,the average risk contagion effects in commodity futures were grea-ter than the hedging effects.At medium frequency scales,hedging-oriented"ripple effects"were more pronounced.Corn,soybean oil,thermal coal,and gold served as hedging centers at low,lower-medium,medium,and high frequency scales,respectively.Iron ore,along with industry chain-related commodities such as methanol,ethylene,and coke,remained relatively stable strong risk centers across all time scales.Additionally,the hedging effects during stock market crashes and trade friction periods exhibited significant lag effects.Therefore,it is recommended to enhance market transparency and credibility to effectively reduce heterogeneous volatility risks in commodity futures and prevent the ensuing"ripple effects."
commodity futuresripple effectbidirectional testingfrequency domain analy-sishigh-frequency data