国际原油价格对国内玉米价格的溢出效应分析——基于VECM-BEKK-GARCH模型

分析了国际原油价格波动对国内玉米价格的溢出效应。研究结果表明:两个市场之间存在明显的信息传导关系;国际原油市场和国内玉米市场之间存在波动溢出,但波动溢出是非对称的,只存在国际原油市场向国内玉米市场的波动溢出,而不存在国内玉米市场向国际原油市场的波动溢出。     

进口快速增长背景下国内外粮食价格波动传递效应实证研究

本文从粮食进口快速增长背景下粮食贸易格局转变视角,利用中国和国际大豆、玉米、小麦和大米的月度价格数据,采用VAR-BEKK-GARCH模型剖析国际粮食价格波动对中国粮食价格的影响和溢出效应。研究发现,国内外大豆价格间存在协整关系,而国内外玉米、小麦和大米价格间不存在显著的协整关系;国内外粮食价格传递效应上存在差异,国内外大豆价格间存在双向的均值和波动溢出效应,国内外玉米价格间存在单向的均值效应和双向的波动溢出效应;国际小麦和大米价格波动传递效应较弱,而中国大米和小麦市场对国际市场具有较强的溢出效应;贸易格局转变形势下,国内外粮价波动溢出效应有所强化,但是粮食市场宏观调控政策一定程度上化解了国际粮食价格波动对中国粮食市场的影响。     

农产品现货与期货价格波动溢出效应研究

中国的农产品期货市场至今已有三十年历史,现有的种类共十三种,大约占上市期货品种数量的二分之一。本文选用中国大豆农产品,建立指数条件异方差模型(E-GARCH)和脉冲响应分析,通过实证研究发现:大豆期货价格市场存在双向溢出效应,在受到外部冲击后,中国大豆期货价格收益增长率波动加剧,但大豆期货价格波动持续性减弱。大豆期货价格对现货价格的冲击,相较于现货价格对农产品期货价格的冲击更为敏感。中国大豆期货市场对现货市场具有价格发现作用,而现货市场对期货市场的影响力较弱。最后针对结论提出政策建议。     

期货市场金融化、投机诱导与大豆期货价格波动——基于CBOT大豆期货市场数据的实证分析

本文基于CBOT大豆期货市场2006年6月至2015年12月期间的月度数据,分时期考察了期货市场金融化与商品期货价格波动之间的关系,并运用AMR模型,论证了投机诱导在期货市场金融化与商品期货价格波动之间的中介效应。研究结果表明,期货市场金融化对期货价格短期波动的影响具有乘数效应,国际投机基金的投机行为造成商品期货市场价格短期波动加剧的同时,对商品期货市场中的实需投资者产生投机诱导,进一步加剧期货市场的价格波动;而由于市场理性预期的存在,期货市场金融化与投机诱导对商品期货的长期价格形成不存在显著影响,商品期货的长期价格依然由实际供求关系主导。     

我国战略性农产品期货市场价格发现功能及效率研究——以大豆为例

本文采用向量自回归模型、Johansen协整分析、Granger因果检验、向量误差修正模型、脉冲响应函数、方差分解等方法,从多个层次分析了以大豆为代表的我国战略性农产品期货价格与现货价格之间的互动关系,定量刻画了农产品期货市场在价格发现中的作用和效率。实证结果显示,我国大豆期货价格与现货价格之间存在长期均衡关系和期货对现货价格的单向引导关系;期现货市场均扮演着重要的价格发现角色,但期货市场在价格发现功能中起着更有效的主导作用,这为我国战略性农产品通过期货市场获取国际定价权奠定了良好基础。     

我国玉米期货市场发现价格功能的实证分析

本文利用协整检验、格兰杰因果检验以及Garbade-Silber模型等方法对我国玉米期货市场的发现价格功能进行了实证分析。结果表明：我国玉米期货价格与现货价格之间存在协整关系，期货价格具有良好的发现价格功能；仅存在从期货价格到现货价格的单向格兰杰引导关系，而现货价格对期货价格不具有格兰杰引导关系；玉米期货市场的发现价格功能中期货价格起着决定性的作用。     

主产地与主销地之间农产品价格联动关系研究——以环北京蔬菜市场为例

农产品价格是联系供给和需求的重要纽带,农产品价格的波动直接影响到供需双方不同主体的利益,具有重要的联动效应。文章以环北京地区的蔬菜市场为例,运用VAR模型、脉冲响应函数和方差分解法进行实证分析,研究主产地与主销地之间的农产品价格传导方向和影响程度,把握地区间农产品价格的联动关系。研究发现,主产地与主销地之间的蔬菜价格存在传导效应,销地市场价格在蔬菜价格波动中具有引导作用,销地市场的蔬菜价格向产地市场的传导效率较高;北京蔬菜价格是影响环北京地区蔬菜价格变动的重要因素,北京在蔬菜流通中具有重要节点作用;销地市场价格波动对产地市场价格变动的贡献度相对较高,销地市场对产地市场具有带动作用。     

中国棉花产业链价格传导机制浅析

分析我国棉花价格与棉花期货价格、棉纱价格在产业链中的价格传导机制,为完善棉花价格形成机制提供参考。借助2017～2021年中国棉花价格指数、中国棉花信息网的棉纱价格信息和郑州棉花期货数据进行实证分析,研究三者之间的传导关系。经过实证分析,发现三者之间存在协整关系,其中棉花价格每变动1%,使棉纱价格变动1.103%、棉花期货价格变动0.265%。我国棉价对棉纱价格存在单向影响,棉花期货对棉花价格存在单向影响关系,棉纱价格与棉花期货之间是互为影响关系。我国棉花现货市场与下游棉纱市场关系日益紧密,棉纱价格与棉花价格两者之间存在引导作用,棉花期货中介效应明显。     

中美农产品价格波动特征及溢出效应研究——基于大豆期货数据的分析

本文以大连商品交易所和芝加哥期货交易所的大豆期货作为中美农产品的代表,运用GARCH-M、EGARCH等模型分别对其日收盘价格数据进行分析,研究其价格波动的特征及溢出效应。结果表明:两国大豆期货收益率序列存在自相关性、异方差性和明显的集聚性;两国大豆期货的价格波动对收益率的影响均不明显;美国大豆期货价格波动具有明显的非对称性,而中国大豆期货价格波动的非对称性并不显著;两市场存在着明显的波动溢出效应,而且中国大豆期货价格的波动对美国大豆期货价格的波动溢出效应更为显著。     

价格支持、政策调整及粮食市场波动

目的 为了估计价格支持政策对不同粮食品种期现货价格波动的直接影响,实证分析和比较了政策及其调整对粮食期现货价格波动实施效果的影响,为深化粮食价格形成机制改革提供一定的理论参考和实证支撑。方法 文章利用稻谷、小麦、玉米和大豆的现货与期货价格日数据,将政策以虚拟变量的形式引入GARCH模型实证分析最低收购价政策、临时收储政策及其调整对平抑粮食期现货市场波动的作用。结果 价格支持政策对粮食价格波动产生了显著影响,最低收购价政策能够明显降低稻谷和小麦现货市场的波动程度,但对期货市场波动的作用则相反;玉米和大豆临时收储政策的取消导致现货市场波动性提高,而对期货市场波动的影响存在差异。结论 价格支持政策具有降低价格波动的作用效果,政策调控效果与实施品种的国内供求及市场形势、国内外市场的联系程度密切相关,政策的完善还需关注对期货市场波动的影响。     

Efficiency tests of agricultural commodity futures markets in China

The efficiency of the Chinese wheat and soybean futures markets is studied. Formal statistical tests were conducted based on Johansen's cointegration approach for three different cash markets and six different futures forecasting horizons ranging from 1 week to 4 months. The results suggest a long-term equilibrium relationship between the futures price and cash price for soybeans and weak short-term efficiency in the soybean futures market. The futures market for wheat is inefficient, which may be caused by over-speculation and government intervention.     

Volatility in Oilseeds and Vegetable Oils Markets: Drivers and Spillovers

Food price volatility has re‐emerged as an important topic of political discussion since the food price crisis of 2007–2008. Different volatility drivers have been identified for different markets in the theoretical and empirical literature. However, there is no comprehensive analysis that considers a large number of potential drivers and investigates their joint effects in a dynamic model of interrelated markets. Our study provides such a volatility analysis for the oilseeds and vegetable oils markets. We use a common GARCH approach and a VAR model to identify volatility drivers and spillover effects. Our results show that exchange rate volatility is very important. However, the hotly debated financialisation of commodity markets is not found to be volatility increasing in our monthly data. Impulse response functions show strong spillover effects. Because many volatility drivers found to be important in other markets have no significant effect in our study, our results suggest that volatility drivers are market specific. This implies that any volatility‐reducing policies need to be designed for the market in question.     

中国农产品期货市场功能发挥的现货市场条件探讨

本文在对期货市场功能发挥和现货市场关系探讨的基础上，从期货市场发现价格和回避风险功能角度，指出农产品期货市场功能发挥所需具备的现货市场条件是：现货市场发达完善和接近完全竞争；进而实证分析影响中国农产品期货市场功能发挥的现货市场条件的因素。主要结论是中国农产品期货市场是在现货市场发育还不充分的情况下产生并发展起来的，不完善的现货市场争件是影响和制约农产品期货市场功能充分发挥的关键因素。     

Hedging Opportunities for Canadian

The unprecedented commodity price volatility in the last decade has resulted in a growing interest in futures trading by farmers. One of the major reasons often provided for the usefulness of commodity futures markets is that they provide a mechanism whereby producers can shift the risk of price change onto others. Interestingly, little research has been conducted on the effectiveness of the WCE as a hedging tool for farmers.
The objective of this paper was to investigate the extent to which the futures contracts for rapeseed, barley and flaxseed can be used by farmers in order to reduce price risk (measured by volatility). Drawing on earlier literature, the theory of hedging was reviewed and formulae for estimating the optimal hedge and the effectiveness of hedging were presented. An empirical analysis determined that the Winnipeg rapeseed, barley and flaxseed futures contracts are very useful in terms of allowing a producer the opportunity to reduce exposure to price risk.     

Futures Markets and Spot Price Volatility: A Case Study

Futures markets, where they exist, can play a crucial role in determining the storage decision in the underlying spot (physical) market. The futures market acts as a conduit for market information and is a gatherer of agents' expectations about the future prospects for the spot market. As such, it is able to provide both price insurance and price discovery roles, the latter of which generates information for spot market traders and allows them to make rational storage decisions. If this were to be the case, then the efficiency of storage is improved which can potentially lead to a reduction in the volatility of spot prices over the marketing season. The existing literature is ambiguous as to whether futures markets can help spot markets price more efficiently. This paper seeks to examine whether this is the case in the British maincrop potato market by evaluating the volatility of spot prices over the period 1969–96 in a “before-after” analysis of the impact of the introduction of futures trading in 1980. The results suggest that the introduction of the futures market has led to a reduction in price volatility, despite some problems in the operation of the futures market itself.     

Price and Volatility Transmission and Market Power in the German Fresh Pork Supply Chain

We investigate the relationship between the transmission of price volatility and market power in the German fresh pork supply chain. We use a theoretical model underpinning this relationship followed by an empirical application that uses monthly farm, slaughterhouse and retail pork price data for the period 2000–2011. We examine both the relationships of market power with price level transmission and price volatility transmission in the chain. We use a vector error correction model and least squares regressions to analyse price transmission and price volatility transmissions, respectively. Results show that retail market power limited both types of transmissions. Competition inducing policy measures coupled with measures that support price risk management initiatives of chain actors are suggested.     

Price formation in the German biodiesel supply chain: a Markov‐switching vector error‐correction modeling approach

Changing linkages between agricultural and energy markets have attracted considerable attention in research and policy discussions during recent years. As one of the largest biofuel markets worldwide, the German biodiesel market is of particular interest. It has grown rapidly since the beginning of the new millennium, with this growth being driven mainly by political interventions. Vertical price transmission channels along the biodiesel supply chain are analyzed in this study. We examine the relationship between diesel and biodiesel prices, and between rapeseed oil, soy oil, and biodiesel prices between 2002 and 2008. Due to pronounced changes in market conditions and the policy framework, a regime‐dependent Markov‐switching vector error‐correction model is used. The regimes are characterized by markedly different price adjustment behaviors. Before 2005 and from late 2007 onward, a regime characterized by the strong orientation of biodiesel prices toward diesel prices dominates. Between 2005 and 2007, biodiesel and rapeseed oil prices are mutually interdependent. Frequent switches between the regimes of the price dynamics during this period indicate a high extent of uncertainty and instability in the market.     

TEMPORAL PRICE RELATIONSHIPS IN THE VANCOUVER RAPESEED FUTURES MARKET AND THEIR IMPLICATIONS TO FARM PRICES*

This paper is concerned with an evaluation of pricing performance in the Canadian rapeseed market. Holbrook Working's model of temporal price relationships in continuous inventory futures markets is used to show that Vancouver rapeseed futures are inverted and biased downward. Prices received by producers are affected since the inverted and biased futures prices are reflected through street price committees in Western Canada.
Cet article cherche àévaluer la fluctuation des prix de vente des Graines de colza sur le marché canadien. L'auteur se sen du modèle de Holbrook Working, qui traite des fluctuations sur un inventaire ďactions continuel, afin re montrer que la vente des actions des Graines de colza sur le marché de Vancouver est renversé. Les prix reçus par les producteurs sont affectés parce que les prix renversés des actions sont réflétés par le prix de vente ďactions non enregistrés sur le marché de ľouest Canadien.     

产业链视角下乳制品价格溢出效应研究——基于VAR-BEKK-GARCH(1,1)模型

奶业产业链是乳制品价格形成的基础,从产业链着手有助于发现乳制品价格溢出效应的本质特征。本文选取牛奶、酸奶、婴幼儿奶粉、老年奶粉作为乳制品的代表,基于2010年5月至2018年5月乳制品产业链月度价格数据,使用VAR-BEKK-GARCH(1,1)模型分析乳制品产业链各环节间的价格溢出效应。研究发现:婴幼儿奶粉产业链上、中、下游价格间存在显著的单向均值溢出效应,而牛奶、酸奶、老年奶粉产业链的中游对上游、下游对中游价格存在显著的单向均值溢出效应;牛奶、酸奶、婴幼儿奶粉、老年奶粉产业链各环节价格在自身和彼此间具有显著双向波动溢出效应,但从显著性水平来看,牛奶产业链和婴幼儿奶粉产业链各环节间的双向波动溢出效应最为明显。