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。     

Using Formula Prices in the Absence of Publicly Reported Prices: An Application for Segregated Early Weaned Pigs

A formula for deriving the price of segregated early weaned pigs using corn, soybean meal, and market hog prices was estimated by equating return on investment for the different phases of production. USDA reported prices were compared with prices derived from this and several other common formulas. Based on several accuracy measures, the estimated formula was better at predicting spot-market prices than other formulas. Producers appear to form price expectations based on futures plus expected basis rather than simply futures or current cash prices. However, the method of choosing price expectations will depend on the risk attitudes of the buyer and seller and their business relationship. Developing pricing formulas based on the framework outlined here (equal returns on investment) has merit for establishing prices in the absence of publicly reported information. However, it is important that users of the formula understand the conceptual framework of how and why it was developed.     

How much of commodity price behavior can a rational expectations storage model explain?

A rational expectations competitive storage model was applied to the U.S. corn market, to assess the aptness of this framework in explaining monthly price behavior in an actual commodity market. Relative to previous models, extensive realism was added to the model, in terms of how production activities and storage costs are specified. By modeling convenience yield, “backwardation” in prices between crop years did not depend on the unrealistic assumption of zero ending stocks. Our model generated cash prices that were distributed with positive skewness and kurtosis, and mean and variance that increased over the storage season, comparable to the persistence and the occasional spikes observed in commodity prices. Futures prices were generated as conditional expectations of cash prices at contract maturity, and the variances of futures prices exhibited realistic time–to‐maturity and seasonal patterns. Model realizations of cash and futures prices over many “years” were used to demonstrate the wide variety of price behaviors that could be observed in an efficient market with a similar market structure, implying that economic and policy implications drawn from short, historical samples of prices could be misleading.     

Information-rich wheat markets in the early days of COVID-19

This paper uses the information implicit in commodity futures and options prices to infer market beliefs about the impact of early-stages COVID-19 on commodity market fundamentals. The particular commodity examined is soft red winter (SRW) wheat, and the timeframe is early February to late March 2020. The analysis highlights various adjustments in the cash and futures price of SRW wheat in light of surging short-run demand from consumer hoarding of staple food products, and a weakening long-run market from growing wheat stocks and an emerging global recession. This split is causing the forward curve to flatten and basis levels to invert. The change over time in the price of options on wheat futures reveals increased price volatility in response to growing uncertainty about the COVID-19 impacts. Similarly, changes in the skewness of the option's volatility smile illustrate a shift in traders’ perception about risk in the right versus left tail of the price distribution.     

How Reliable Are Hog Futures as Forecasts?

The Chicago Mercantile Exchange hog futures contract was revamped in 1997 and it is one of the largest futures markets for a nonstorable commodity. The literature is divided on whether or not futures prices for nonstorables provide reliable forecasts of cash prices. We find that from 1998 to 2004, the hog futures market was an unbiased predictor of cash prices.     

Renewable versus nonrenewable resources: an analysis of volatility in futures prices

This study outlines a new approach for differentiating commodity futures based on their exhaustibility. Various aspects of volatility in the futures prices of renewable resources (palm oil, coffee, soya beans, rice, wheat and corn) and nonrenewable resources (zinc, aluminium, natural gas, gold, crude oil and copper) are studied, exploring whether volatility is greater in the former than in the latter. We use a generalised autoregressive conditional heteroskedasticity (GARCH) model to test our main hypothesis that the volatility in futures prices for renewable resources has recently been equal to or greater than the volatility in futures prices for nonrenewable resources. Our key findings suggest that futures prices for some renewable resources have greater variance than those for benchmark crude oil in a simulated GARCH series. We extend our analysis using a nonlinear vector smooth transition autoregressive (VSTAR) model to test for the existence of a shifting‐mean tendency in the commodity series that we researched. We show that transition from a stable to a volatile regime is more abrupt for renewable resources.     

Could packers manipulate spot markets by tying contracts to futures prices? And do they?

Some producers, policy makers, and researchers claim that packers influence cash prices through contracts tied to futures prices. This paper provides a theoretical and empirical study on the price effects of contract-pricing terms linked to futures price and the related formula pricing terms linked to a cash price. We show that contract-pricing terms tied to a cattle futures price can theoretically be used to reduce the cash price. Furthermore, the model demonstrates that such tied-to-a-futures-price contract-pricing clauses and the related tied-to-a-cash-price formula pricing clauses can be substitutable tools for packers to depress the cash cattle price. Nevertheless, although empirical results are consistent with the predictions of the theoretical model they show that while such manipulations may occur, their market power impact appears quite small.     

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.     

Measuring the Volatility of Wheat Futures Prices on the LIFFE

Agricultural prices rose dramatically in 2007 and have subsequently fluctuated at high levels. This paper estimates the volatility of daily wheat futures prices on the Euronext/London International Financial Futures and Options Exchange for 1996–2012 using an exponential generalised autoregressive conditional heteroscedasticity model with a constant (price) elasticity of variance (CEV) and a broken trend. Results show that volatility is highly persistent; there is a structural break in volatility in June 2007 when volatility rose by 10%; subsequently, the wheat futures price has become more volatile; and the CEV is 0.04.     

Agricultural Producer Price Expectations

Producer price expectations underlie much of agricultural supply analysis. While producer price expectations would ideally be discovered experimentally, this is too costly. Instead, producer price expectations are usually represented in agricultural supply analysis by easily obtained hypothesized expectation formulations. In most cases, the hypothesized expectation formulations are functions of past prices. However, other formulations are sometimes used, such as current cash and futures prices, or initial payments in the case of grains marketed by the Canadian Wheat Board. This paper compares actual producer price expectations with a variety of hypothesized expectation formulations for wheat and canola in Saskatchewan. A test developed by Granger is used to determine the proxy models that are significantly dominant. The model that dominates as a proxy in the case of wheat price expectations is the two-year declining-weight moving average. The two models that dominate as a proxy in the case of canola price expectations are the first-order autoregressive and, as well, the two-year declining-weight moving average. There is no significant difference between the two models. Somewhat surprising is the performance of formulations based on futures prices. These formulations perform very poorly in representing producers' price expectations, even though they are found to be among the most accurate predictors of actual commodity prices. An even more interesting observation is the performance of the futures price model in the canola market. Even though the November contract in January explains very little of the variation in the actual commodity prices for that year, its error in predicting canola prices is not significantly greater than that of the best performing, the four-year declining-weight moving average, based upon the root mean squared error criterion.     

Developing Hedging Strategies for Québec Hog Producers under Revenue Insurance

The paper investigates the optimal hedging strategies of Québec hog producers when they participate in a publicly funded revenue insurance program known as ASRA (Régime d'assurance-stabilisation des revenus agricoles). A forecast model of local cash and futures prices is built and Monte Carlo methods are used to derive the optimal futures and option positions of Québec hog producers. The positive correlation between forecasts of futures and cash spot prices induces positive sales of futures and put options to hedge price risk. ASRA provides put options to hog producers at actuarially advantageous terms. Producers can increase the expected utility of profits by selling back a portion of these put options using financial markets. Options are attractive to manage price risk given the nonlinearity in the profit function induced by the revenue insurance scheme. Speculative incentives to use futures and options are also discussed in the context of ASRA.     

Price discovery in a private cash forward market for lumber

Cash forward contracting is a common, and often preferred, means of managing commodity price risk in many industries. Despite this, little is known about the performance of cash forward markets, in particular the role they play in price discovery. The US lumber market provides a unique case for examining this issue. The Bloch Lumber Company maintains an active cash forward market for many lumber products, and publishes benchmark forward prices on their website and disseminates these prices to data vendors. Focusing on 2×4 random lengths lumber and 7/16 oriented strand board, this research examines the lead–lag relationships between the 3-month forward prices published by Bloch Lumber, representative spot prices, and lumber futures prices at the Chicago Mercantile Exchange. Results suggest that at least for 2×4 random lengths lumber, the forward prices published by Block Lumber lead both the spot price and futures price, suggesting that this private cash forward market provides some level of price discovery in the lumber markets.     

Is a Futures Market Viable in Turkey? The Case of a Cotton Futures Market

Abstract

Many countries as they reduce price controls develop an interest in futures markets as a way to manage risk. This article explores the potential of using existing futures markets to hedge cotton in Turkey. Futures prices in New York and Liverpool are not cointegrated and only weakly correlated with cash prices in Izmir. Thus, existing futures markets have limited ability to reduce the risk faced by the cotton industry in Turkey. While there are obstacles to overcome, there does appear to be a potential demand for a cotton futures market in Turkey.     

How financial investment distorts food prices: evidence from U.S. grain markets

Convergence between commodity futures prices and the underlying physical assets at each contract's expiration date is a pivotal condition for the market's functioning. Between 2005 and 2010, convergence failed for several U.S. grain markets. This article presents a price pressure‐augmented commodity storage model that links the scale of nonconvergence to financial investment channeled through indices, which are traded in commodity futures markets. The model is empirically tested, using Markov regime‐switching regression analysis. Regression results strongly support the model's predicted link between index investment and the extent of nonconvergence for three grains traded at the Chicago Board of Trade: wheat, corn, and soybeans.     

期货市场、货币供应量对农产品价格波动的影响——基于对小麦、玉米、大豆粮食品种的实证分析

近年来我国农产品价格波动频繁,特别是短期内小宗农产品价格波动剧烈,在一定程度上影响了农业生产秩序和物价稳定.基于2010年1月至2014年4月小麦、玉米和大豆价格的月度数据,采用VAR模型实证分析了农产品期货价格和货币供给的增长在影响农产品价格波动方面的差异性,并提出稳定农产品价格异常波动的相关策略及方法.     

Insights from Anticipatory Prices

Contemporaneous observations on expected supply and on prices of post‐harvest futures contracts for corn are used to estimate expected demand relationships. These equations are used to estimate the prices of the post‐harvest contracts based on new supply estimates. Each estimate can be compared with a corresponding futures price, i.e. the market forecast. The differences help discern the market expectations about the expected demand for the new crop relative to historical experience, which can help support outlook analyses. We find that in recent years, a 100 million bushel change in the expected supply of corn results in about a 6 cent per bushel negative change in the price of December corn. The discussion also deepens understanding of the term ‘anticipatory prices’ as defined by Holbrook Working in his 1958 work.     

Structural Breaks and the Relationship between Barley and Wheat Futures Prices on the London International Financial Futures Exchange

Co-movement between futures prices can arise when commodities are substitutes. Counterintuitively, Dawson and White fail to find a significant long-run link between feed barley and wheat prices on the London International Financial Futures Exchange. This relationship is re-examined using  Johansen, Mosconi, and Nielsen's co-integration procedure that permits structural breaks. Results show evidence of co-integration and hence price discovery. There is a significant break in October 2000 following Common Agricultural Policy intervention price reductions, the barley–wheat futures market is perfectly integrated, and the barley price Granger-causes the wheat price. Modeling structural breaks in price relationships appears important.     

Do wheat futures returns exhibit long‐range dependence?

The efficient market hypothesis, where asset prices follow a random walk and incorporate all relevant information, is often invoked in financial economics. There is some evidence however to suggest that some asset prices do not follow random walks but display long‐range dependence. Such systematic behavior of past returns is of interest to traders. This article examines long‐range dependence in wheat futures prices using rescaled range analysis and the Hurst exponent. Since this estimate is biased when long‐range dependence is absent and its distribution is unknown, a Monte Carlo simulation approach is proposed. Results show that wheat futures prices show no evidence of long‐range dependence and there are no profitable trading rules.     

Price Risk Management for Peanut Meal

Abstract

Peanut meal is cross-hedged with soybean meal using peanut meal cash prices and soybean meal futures prices. Hedge ratios are obtained for a 3-year and a 6-year period model. The data is from 1993 to 2000, with the 2000 data used for evaluation. All hedge ratios are significant and the 3-year period model's results suggest that long term data sets have less explanatory power than short-term hedge ratios. Evaluation results indicate positive gains for cross-hedged poultry producers and/or peanut producers. The empirical analyses suggest that soybean meal futures can be used as a potential cross-hedging vehicle for peanut meal.     

Destabilizing role of futures markets on North American hard red spring wheat spot prices

The objective of the paper is to determine if the futures prices of hard red spring wheat (HRSW) have stabilizing or destabilizing impact on spot HRSW price in North America. Several important results emerge from thorough empirical analysis. First, both Granger causality tests and directed acyclic graph algorithms (DAGs) point to two-way causality between futures and spot HRSW prices and thus endogeneity in both prices formation. To the contrary, both procedures suggest that ending stocks are exogenous to spot and futures HRSW prices. Both vector error correction model and impulse response functions point to a large and long-lasting impact of a shock to futures price on spot price level. Finally, variance decomposition analysis indicates that futures prices are responsible for the bulk of spot price volatility in both short and long run. Our result is consistent with those of theoretical models suggesting that when production (supply side) is the dominant disturbance, spot price is destabilized in both the short and the long run by futures prices. An important implication of this research is the need for alternative market mechanisms or alternative farm policy measures that would mitigate price risk and ensure sustainable farming of American HRSW farmers.