Study On The Fluctuation Characteristics And Spillover Effects Of Corn Spot Rrices In China

Food is the basis of people’s livelihoods and food security is a cornerstone of a country’s overall security and stability and an important part of the national security system.However,in recent years,food price fluctuations have become more frequent and have had a greater negative impact on the national economy and people’s livelihoods.As one of the three major staple foods,the price fluctuations of maize are closely related to the issue of food security and may have an increasing impact on the national economy.The marketisation of maize has started after the reform of the reserve policy and the linkages with other markets are being strengthened,increasing the risk of price fluctuations and the possibility of spreading the risk to the outside world.In addition,the price volatility characteristics and spillover effects of maize appear to have taken on new characteristics during the COVID-19 epidemic outbreak.Therefore,exploring the new characteristics of maize price volatility and spillover effects in the context of the COVID-19 epidemic will help to understand the impact of the risk of price volatility in the agricultural market during emergencies on the national economy and people’s livelihoods,provide partial reference for government and producer decision-making,and in turn provide theoretical support to promote the stable and healthy development of agricultural market in China.In terms of theory,this paper combines economic volatility theory,local equilibrium theory and price transmission theory to construct a research framework on the characteristics of maize price volatility and spillover effects.Through theoretical analysis,we find that supply and demand factors and emotional factors brought about by unexpected events are important causes of long-and short-term fluctuations in maize prices;secondly,we analyse the external spillover mechanism of the risk of maize price fluctuations from both horizontal and vertical paths,and propose that the COVID-19 epidemic has enhanced the external spillover effect of the maize market.In the empirical evidence,this paper uses price decomposition methods and GARCH-type models to explore the characteristics of long-and short-term fluctuations in maize prices,and further employs the VAR-BEKK-GARCH model to investigate the spillover effects of maize price volatility with the horizontal substitution market and the vertical industry chain market,while using the implementation of the COVID-19 epidemic "Category B infectious diseases are managed as Category A" The sample is divided at the nodal point to also discuss the impact of the COVID-19 epidemic on the spillover effect of maize price volatility.The following conclusions are drawn:Firstly,maize price volatility in the long term as a whole is fluctuating in an upward trend,under the influence of non-market shifts in supply and demand conditions into "up-down-up" three stages;secondly,the seasonal effect of maize price volatility is significant,but with the gradual maturation of maize market reforms and production,the seasonal effect is significantly weaker than before;thirdly,the maize market is characterised by significant irregular fluctuations and prices are highly influenced by unforeseen events;fourthly,there is a significant agglomeration effect,a "risk premium" feature and a negative asymmetric feature in the short-term fluctuations of maize prices,which means that there is more speculation in the maize market and market players are more sensitive to bearish news;fifthly,there are significant external spillovers from the maize market,which implies a strong spread of price volatility risks;sixthly,the spillover effect between markets is enhanced by the new pneumonia epidemic,which means that if the maize market is hit by a large impact in the context of an unexpected event,the diffusion effect of the risk of price volatility will be stronger when catalysed by negative sentiment.Based on the above analysis,this paper puts forward countermeasure suggestions from the perspectives of corn supply chain construction,policy environment,strengthening financial supervision and building an information platform.