国际大米价格波动对国内大米价格的传递效应研究

［目的］国际粮食价格波动会对国内粮食价格产生影响，其影响程度和途径一直是农产品价格领域的研究热点。［方法］基于2002年1月至2017年6月的月度数据，运用Johansen协整检验和向量误差修正模型检验了国际大米价格与国内大米价格的长期均衡与短期输入关系，在考虑国内大米价格形成机制的基础上分析了国际大米价格的影响程度，并进一步检验了大米与其他粮食品种价格间的整合关系。［结果］（1）国内大米价格与国际大米价格保持长期均衡关系，短期内国内大米价格对国际大米价格波动的弹性为00226。（2）国际大米价格对国内大米价格具有显著的影响，在控制其他变量不变的前提下，国际大米价格每上涨1%，国内大米价格会上升约01%。（3）Johansen协整检验表明大米会与其他粮食品种价格保持长期整合关系，国际大米价格上涨可能会通过间接渠道传递至国内大米市场。［结论］因此不仅需要关注国际大米价格对国内大米价格的影响，还需要关注其他粮食品种对大米价格的影响。     

The impact of food price increases on caloric intake in China

World food prices have increased dramatically in recent years. We use panel data from 2006 to examine the impact of these increases on the consumption and nutrition of poor households in two Chinese provinces. We find that households in Hunan suffered no nutrition declines. Households in Gansu experienced a small decline in calories, though the decline is on par with usual seasonal effects. The overall nutritional impact of the world price increase was small because households were able to substitute to cheaper foods and because the domestic prices of staple foods remained low due to government intervention in grain markets.     

最低收购价政策调整对我国粮食安全的影响以稻谷为例

目的 最低收购价政策实施以来,在稳粮价、促生产、保粮安的同时,也产生了显著的负面影响,探索以市场机制为核心的粮食价格支持政策改革势在必行。方法 文章以稻谷为例,通过构建局部均衡模型,模拟逐渐下调最低收购价、取消最低收购价、取消最低收购价并大幅增加农业补贴等方案对我国稻谷的产量、总消费、库存和净进口等方面的影响,进而探究最低收购价政策调整对我国粮食安全的影响。结果 （1）下调稻谷最低收购价,对稻谷市场价格、总产量和总消费的影响较小,而对库存和净进口量的影响较大;（2）取消最低收购价,虽然能大幅度减小国内外差价、库存量和进口量,但短期内也会显著减少稻谷产量,对我国的粮食供给安全带来了巨大冲击;（3）取消稻谷最低收购价,并大幅度提高了农业补贴后,稻谷总产量下降水平明显减少,既解决了托市收购带来的负面影响,也降低了取消托市收购对粮食供给安全的冲击。结论 最低收购价政策的支持效应显著,为充分保障国内粮食安全,在推行粮食市场化改革时,应首先考虑小幅度下调最低收购价,而不是一次性取消最低收购价政策;同时,要配套相应的补贴政策,优化农业补贴结构,来保障粮农的种植积极性。     

中国粮食价格波动的成因及经济效应分析

选取1978—2011年的年度数据,运用协整对中国粮价波动的成因进行实证。结果表明：粮食生产量、农业生产资料价格指数、居民消费价格指数、粮食消费量、国际粮食价格、广义货币量和粮食库存量对粮食生产价格影响显著;粮食生产量、居民消费价格指数、粮食净进口量对粮食零售价格影响显著。而粮价波动的经济效应：2种粮食价格对粮食产量的影响不同;粮价上涨农民得到的很少;不能确定物价与2种粮食价格是否有关。最后提出了相关政策建议。     

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。     

粮食、食品价格和CPI的VAR实证研究

综述了目前国内关于粮食价格、食品价格对CPI的影响机制的研究.选取2001年7月至2012年12月的月度数据,通过VAR进行了粮食冲击效应分析,采用Johansen检验进行了三者因果的验证,合理解释了食品价格和粮食价格、CPI三者之间的影响关系.结论：在研究的时间段中,粮食价格和食品价格的增长都会引起物价水平的增长;物价水平的上涨也会影响到粮食价格.但是,物价水平对食品价格、粮食价格对食品价格的变化却影响不明显.     

新一轮国际粮食价格上涨：原因及对中国市场的影响

目的 随着中国粮食进口不断增加,国内外市场联系越来越紧密。2020年下半年以来,国际市场粮食价格快速上涨,对国内粮食市场产生一定影响,分析国际市场价格上涨的原因和影响对确保国内粮食供应稳定、保障国家粮食安全具有重要意义。方法 文章分析了2019年以来小麦、大米、玉米、大豆4种粮食产品的国内外价格走势,从供需状况、贸易政策、气候变化等因素分析国际市场价格波动的原因,并探讨了国际价格对国内价格的影响。结果 当前全球主要粮食品种供应充足,库存仍处于较高水平,此轮国际粮食价格上涨主要是受到美国等发达国家宽松的货币政策以及疫情后全球消费逐步回暖的影响;但国际市场价格上涨对中国市场的影响总体有限,国内小麦、大米、玉米价格上涨的主因是国内消费回暖和生猪产能恢复带动的饲用需求快速增长,油用大豆受国际市场的影响较大。结论 为稳定国内粮食市场,避免国际市场的冲击,中国要进一步提升粮食综合生产能力,强化科技支撑,加强粮食储备管理,健全政策支持体系,并引导居民建立科学的消费观念。     

Competitive Storage,Biofuels and the Corn Price

The use of corn as an ethanol feedstock has been stimulated by US biofuels policy. This has changed both the position and the slope of the corn demand curve and increased the pass-through from crude oil to corn prices. The principal constraints on ethanol consumption and production have been regulation (the biofuels mandate), capacity constraints in ethanol refining and the blend wall, which puts a ceiling on the ethanol content of gasoline. The incidence of these constraints has varied over time. We model these impacts within the competitive storage model using structural break regression analysis. Our analysis shows that the pass-through has varied over time in relation to the share of ethanol in total US corn use. Our analysis provides robust empirical evidence of an increase in the pass-through from crude oil to corn prices over the period from the start of the century to a high level over 2004–2008 when corn use in ethanol was growing very fast. This enhanced sensitivity was driven by competition for corn as an ethanol feedstock with stock demand exerting strong upward pressure on the corn price.     

中国薯类燃料乙醇发展现状与前景

玉米等粮食价格上涨的压力,导致中国开始寻求以非粮食作物为原料的燃料乙醇生产。利用薯类作物特别是木薯生产燃料乙醇在成本效益等经济方面有较大的优势,未来发展潜力巨大。但是目前薯类燃料乙醇产业在中国的发展还处于初级阶段,主要的限制条件是缺乏先进的生产技术和设备和优良的原料品种,另外也受市场容量和市场进入的局限,其发展规模在一段时期内还相对较小。随着中国高速的经济发展和技术进步的推动,薯类作物将会在燃料乙醇生产中发挥重要作用。     

Bayesian Estimation and Selection of Nonlinear Vector Error Correction Models: The Case of the Sugar-Ethanol-Oil Nexus in Brazil

Nonlinear adjustment toward long-run price equilibrium relationships in the sugar-ethanol-oil nexus in Brazil is examined. We develop generalized bivariate error correction models that allow for cointegration between sugar, ethanol, and oil prices, where dynamic adjustments are potentially nonlinear functions of the disequilibrium errors. A range of models are estimated using Bayesian Monte Carlo Markov Chain algorithms and compared using Bayesian model selection methods. The results suggest that the long-run drivers of Brazilian sugar prices are oil prices and that there are nonlinearities in the adjustment processes of sugar and ethanol prices to oil price but linear adjustment between ethanol and sugar prices.     

Price Relationships in Processors' Input Market Areas: Testing Theories for Corn Prices Near Ethanol Plants

This study examines corn pricing in the vicinity of processing plants. We develop and test several price-distance models for cargo, insurance and freight (CIF) plant pricing in the presence of varying degrees of exporter competition, and for discriminatory free-on-board (FOB) pricing at the farm. The price-distance functions describing spatial prices near processing plants all depend on local transport costs. But the pricing system (CIF or FOB) and the extent of local competition define the level and spatial rate of change in prices.Estimations of an empirical price-location function for Iowa during the spring of 2003 suggest that prices near the plants of four conventional businesses conform to the CIF pricing model. But prices near producer-owned firms or farmer cooperatives failed to show any statistically significant effect on nearby prices. One plant had a price-distance function that resembled FOB pricing.     

Nonlinearities in the U.S. corn‐ethanol‐oil‐gasoline price system

We use a smooth transition vector error correction model to assess price relationships within the U.S. ethanol industry. Monthly ethanol, corn, oil, and gasoline prices from 1990 to 2008 are used in the analysis. Results indicate the existence of long‐run relationships among the prices analyzed. Strong links between energy and food prices are identified.     

The impact of OECD biofuels policies on developing countries

OECD countries’ biofuels policies, derived from energy and environmental legislation and activated by high oil prices, were the primary cause of not only the sudden spike in grain and oilseed prices in 2007–2008 but also of the ensuing price volatility. Even though developing countries have a comparative advantage in biofuels production, they were shut out of rich countries’ biofuel markets by trade discriminating biofuels policies. Developing countries would not have been able to take full advantage of the price spike in the short run anyway given the low supply elasticities and the long time required for biofuel production to come online, unlike for corn‐ethanol. The controversy over the right price of food is misplaced and policy makers should instead focus on improving biofuels policies, which like their counterpart agricultural policies in previous decades, have damaged the welfare of developing countries.     

THE EFFECTS OF FLEXIBLE EXCHANGE RATES ON AUSTRALIAN WOOL PRICES*

The implication of price stabilisation under a volatile exchange rate is an increasingly volatile price denominated in a foreign currency. Time series analysis is used to model the relationship between exports, prices and AWC stocks. This model is used to assess the distribution of the impact of exchange rate shocks on prices denominated in local and foreign currencies. It is found that the AWC has significantly reduced the impact of exchange rate shocks on domestic prices.     

粮食价格波动对农民增收的影响探析——以河南省为例

粮食价格对农民收入至关重要,是农民维持基本生活的重要保证。文章在分析我国粮食价格波动的历史轨迹的基础上,阐述了农民收入的构成,并对粮食价格波动对农民增收造成的影响进行研究。结果表明:粮食价格波动会影响农民收入水平,进而影响农民的农业生产积极性;粮食价格下降,会促进非农就业的工资收入,进而提升农民收入水平,粮食价格波动对相关工业品价格上涨的影响较小。并从加强政府引导、加快农业产业化进程、建立健全粮食价格稳定长效机制、加强粮食流通体系建设等方面提出稳定粮食价格的关键策略,以期为我国粮食安全及农民增收提供一定的理论参考。     

The Welfare Economics of a Biofuel Tax Credit and the Interaction Effects with Price Contingent Farm Subsidies

A framework is developed to analyze the effects of a biofuel consumer tax exemption and the interaction effects with a price contingent farm subsidy. Ethanol prices rise above the gasoline price by the amount of the tax credit. Corn farmers gain directly while gasoline consumers only gain from any reduction in world oil prices due to the extra ethanol production. Domestic oil producers lose. Historically, the intercept of the ethanol supply curve is above the gasoline price. Hence, part of the tax credit is redundant and represents "rectangular" deadweight costs that dwarf triangular deadweight cost measures of traditional farm subsidies.     

The impact of grain self‐sufficiency regime on regional welfare and agricultural productivity in China

The nineties’ agricultural reforms in China that were aimed at deregulating the agricultural market eventually resulted in a huge drop in agricultural production and a high rate of inflation in agricultural input prices; this apparently motivated the government to introduce the grain self‐sufficiency regime in 1998. We examine how and to what extent this reform affected the productivity and welfare of grain farmers in China at the regional level. We find that the price regulations that destroyed the incentive to exert more effort adversely affected the growth in agricultural productivity but contributed to the growth in farmers’ welfare. Although the price regulations resulted in short‐term improvement in welfare across all the regions, in the long run such regulations can potentially result in larger drop in agricultural production because of its negative impact on the incentives to produce more.     

The Effect of Energy Price Increases on the U.S. Livestock Sector

This study is unique and crucial to the current time period because of the recent high energy price escalation. The uniqueness of this study pertains to the void in energy impact research of the agricultural sector, more specifically to livestock. The U.S. Department of Energy has models estimating economy-wide impacts, but not the specific impacts on agriculture. The Iowa State study concentrated on the grain sector.
The results presented here indicate that energy price increases will have substantial effects on livestock prices and production. Energy price increases will also result in differential impacts on livestock commodities (with poultry and eggs having the largest price and production effects). Furthermore, the multi-period framework enables the livestock model to capture lagged production responses. Noticeable is the higher impacts occurring in the third and fourth years.
In the future, higher energy costs may induce changes in U.S. production, processing and distribution patterns of livestock commodities. The highly vertically integrated poultry and egg industries may begin shifting production locations away from the colder northern regions to areas with more temperate climates. For industries like beef, pork and dairy, there may be increased range production to reduce impacts from higher feed costs. For all industries, closer proximity of processing plants to major livestock producing areas may occur.     

Why does on-farm storage fail to mitigate price volatility?

We analyze the role of farm stock management on price volatility under liquidity constraints and heterogeneous price expectations. In commodity markets, speculative behaviors by stockholders tend to reduce price volatility, but this is not the case in certain agricultural markets, where speculation by farmers regarding decisions to sell or store grain is subject to liquidity constraints and heterogeneous price expectations. Like stockholders, most farmers sell grain if they expect a price drop in the near future, but unlike stockholders, they are not necessarily able to purchase grain if they expect a price increase in the next period. Heterogeneous price expectations can also lead to suboptimal storage decisions, further increasing price volatility. For these reasons, the storage management behavior of farmers often fails to mitigate price drops in the way that speculation by stockholders does. We merge historical data on maize prices and household storage collected in Burkina Faso in order to build a dynamic panel over the 2005–2012 period. We show that carryover from one season to the next is associated with unexpected price drops during the preceding lean season and that carryover is associated with more frequent unexpected price drops following the subsequent post‐harvest season.     

Applying cointegration and error correction to measure trade linkages: maize prices in the United States and Mexico

The impact of U.S.‐grown maize on Mexican markets is a subject of heated debate, and is complicated by limited substitution between white and yellow maize as well as regional price differences within Mexico. This article improves on previous analyses using a detailed data set of white maize prices reported weekly in 11 states across Mexico from 1998 through 2005. Using cointegration analysis and the error‐correction model, we find that prices between the United States and Mexico do not share a common long‐run relationship. Within Mexico, prices in Michoacán and Oaxaca are only weakly related with prices in neighboring states, whereas prices in Sinaloa and Jalisco exert considerable influence on prices elsewhere in Mexico. We conclude that, despite North American Free Trade Agreement (NAFTA), white maize prices in Mexico are determined by local conditions including particularly the degree of integration to other regions within Mexico.