Long memory and structural breaks in commodity futures markets

This study employs daily data for 14 commodities and three financial assets 1990–2009 to explore the impact of the time series properties of the futures‐spot basis and the cost of carry on forward market unbiasedness. The main result is that the basis of 16 assets exhibits both long memory and structural breaks. The long memory in the basis is robust even to the use of break‐adjusted data. It implies that the cost‐of‐carry has long memory which the empirical results confirm using the interest cost as a proxy. These new findings suggest that the forecast error has long memory and are inconsistent with unbiasedness. They could be consistent with a weaker version of market efficiency in the presence of a fractionally integrated, time‐varying risk premium but they could also be rationalized by priced noise trader risk with limits to arbitrage in less than fully efficient markets. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark     

New evidence on the forward unbiasedness hypothesis in the foreign‐exchange market

A large empirical literature has tested the unbiasedness hypothesis in the foreign‐exchange market with the use of forward exchange rates. This article amends the conventional testing framework to exploit the information in currency options, with a newly constructed data set for three major dollar exchange rates. The main results are that (a) tests based on stationary regressions suggest that options provide biased predictions of the future spot exchange rate, and (b) co‐integration–based tests that are robust to several statistical problems afflicting stationary regressions and allow for endogeneity issues arising from a potential omitted risk premium term are supportive of unbiasedness. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:627–656, 2006     

A first look at the empirical relation between spot and futures electricity prices in the United States

In this article we investigate the statistical properties of wholesale electricity spot and futures prices traded on the New York Mercantile Exchange for delivery at the California–Oregon Border. Using daily data for the years 1998 and 1999, we find that many of the characteristics of the electricity market can be viewed to be broadly consistent with efficient markets. The futures risk premium for 6‐month futures contracts is estimated to be 0.1328% per day or about 4% per month. Using a GARCH specification, we estimate minimum variance hedge ratios for electricity futures. Finally, we study the dynamic relation between spot and futures prices using an Exponential GARCH model and between the spot and futures returns series using a vector autoregression. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:931–955, 2003     

Normal backwardation is normal

Traditionally, constant expected return asset pricing models are used to assess the presence of a futures risk premium and the validity of the normal backwardation theory. In the light of recent evidence regarding the presence of time variation in expected futures returns, such an approach may lead to incorrect inferences on the applicability of the Keynesian hypothesis. This article therefore allows for variation through time in expected futures returns and offers some strong evidence in favor of the normal backwardation and contango theories. © 2000 John Wiley & Sons, Inc. Jrl Fut Mark 20:803–821, 2000     

Time‐varying jump risk premia in stock index futures returns

This study tests the presence of time‐varying risk premia associated with extreme news events or jumps in stock index futures return. The model allows for a dynamic jump component with autoregressive jump intensity, long‐range dependence in volatility dynamics, and a volatility in mean structure separately for the normal and extreme news events. The results show significant jump risk premia in four stock market index futures returns including the DAX, FTSE, Nikkei, and S&P500 indices. Our results are robust to various specifications of conditional variance including the plain GARCH, component GARCH, and Fractionally Integrated GARCH models. We also find the time‐varying risk premium associated with normal news events is not significant across all indices. © 2011 Wiley Periodicals, Inc. Jrl Fut Mark 32:639–659, 2012     

A STRUCTURAL RISK‐NEUTRAL MODEL FOR PRICING AND HEDGING POWER DERIVATIVES

We develop a structural risk‐neutral model for energy market modifying along several directions the approach introduced in Aïd et al. In particular, a scarcity function is introduced to allow important deviations of the spot price from the marginal fuel price, producing price spikes. We focus on pricing and hedging electricity derivatives. The hedging instruments are forward contracts on fuels and electricity. The presence of production capacities and electricity demand makes such a market incomplete. We follow a local risk minimization approach to price and hedge energy derivatives. Despite the richness of information included in the spot model, we obtain closed‐form formulae for futures prices and semiexplicit formulae for spread options and European options on electricity forward contracts. An analysis of the electricity price risk premium is provided showing the contribution of demand and capacity to the futures prices. We show that when far from delivery, electricity futures behave like a basket of futures on fuels.     

Fama–French in China: Size and Value Factors in Chinese Stock Returns

We investigate the size and value factors in the cross‐section of returns for the Chinese stock market. We find a significant size effect but no robust value effect. A zero‐cost small‐minus‐big (SMB) portfolio earns an average premium of 0.61% per month, which is statistically significant with a t‐value of 2.89 and economically important. In contrast, neither the market portfolio nor the zero‐cost high‐minus‐low (HML) portfolio has average premiums that are statistically different from zero. In both time‐series regressions and Fama–MacBeth cross‐sectional tests, SMB represents the strongest factor in explaining the cross‐section of Chinese stock returns. Our results contradict several existing studies which document a value effect. We show that this difference comes from the extreme values in a few months in the early years of the market with a small number of stocks and high volatility. Their impact becomes insignificant with a longer sample and proper volatility adjustment.     

Market efficiency among futures with different maturities: Evidence from the crude oil futures market

Although many studies have investigated market efficiency of spot and futures prices, that among futures with different maturities has not been studied extensively. In this study, market efficiency and unbiasedness among such futures are defined and the concept of “consistently efficient (or consistently efficient and unbiased) market within n‐month maturity” is introduced. According to this definition, market efficiency and unbiasedness among WTI futures with different maturities are tested using cointegration analysis, and short‐term market efficiency, using an error correction model and GARCH‐M‐ECM. The results show that WTI futures are consistently efficient within 8‐month maturity and consistently efficient and unbiased within 2‐month maturity. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark 31:487–501, 2011     

Predicting exchange rate returns

We test whether forward premiums predict spot exchange rate returns for 16 currencies. We apply a recently developed time series predictability test that allows us to model data features including heteroskedasticity in forward premium. We discover return predictability for 75% (12/16) of currencies in our sample. Trading strategies show that investors can make more profits from our proposed forward premium model compared to a random walk model and foreign exchange carry trade model.     

Price discovery in the options markets: An application of put‐call parity

This study investigates the relative rate of price discovery in Taiwan between index futures and index options, proposing a put‐call parity (PCP) approach to recover the spot index embedded in the options premiums. The PCP approach offers the benefits of reducing model risk and alleviating the burden of volatility estimation. Consistent with the trading‐cost hypothesis, a dominant tendency is found for futures and a subordinate but non‐trivial price discovery from options. The relative weight of options price discovery is sensitive to the methodology employed as the means of inferring the option‐implicit spot price. The empirical evidence suggests that the information contained in the PCP‐implied spot encompasses that provided by the Black‐Scholes‐implied spot. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:354– 375, 2008     

Mean Reversion and the Comovement of Equilibrium Spot and Futures Prices: Implications from Alternative Data‐Generating Processes

The comovements of spot and futures prices are characterized by six binary variables, including the term structure curvature of futures prices. These variables are used to uniquely identify 48 possible comovement patterns. Among them, 24 cases are associated with mean reversion, which is defined as a state when spreads between futures and spot prices are shrinking. These pattern frequencies are then calculated on a daily basis with the futures prices of 10 commodities, including precious metal, agricultural, and financial commodities. The results are further compared to simulation output from three data‐generating processes: a bivariate pure random walk, a mixed random walk with first‐order autoregression (AR(1)), and an error‐correction representation. The mean‐reverting frequencies for all 10 commodities are about 50%. Around half of the time, spot and futures prices are moving toward each other, and the rest of the time they move in the same direction. The symmetry of these results implies that the existence of substantial shocks originated from futures markets; thus, this is consistent with the risk premium view of futures trading. Also, although all simulation models produce similar mean‐reversion frequencies, the patterns of comovements of spot and futures prices are different, and the price dynamics depend heavily on whether the market is dominant contango or backwardation. Furthermore, the error‐correction model outperforms the random‐walk model for agricultural commodities, and the mixed random walk with AR(1) is hardly distinguishable from the pure random walk. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark 21:769–796, 2001     

Time‐varying market price of risk in the crude oil futures market

In this study, a three‐factor model of crude oil prices is estimated, which incorporates a time‐varying market price of risk. The model is able to accurately capture the term structure of futures prices with evidence suggesting that risk premiums in the crude oil market are time‐varying. Using the cross‐section of futures prices, we estimate a time‐series of the market price of risk in the crude oil market implied by the model. We find that the risk premiums in the crude oil market are driven by the same risk factors as equity and bond markets. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark 31:779–807, 2011     

Bias and backwardation in natural gas futures prices

This paper tests the fair‐game efficient‐markets hypothesis for the natural gas futures prices over the period 1990 through 2003. We find evidence consistent with the Keynesian notion of normal backwardation. Regressing the future spot prices on the lagged futures prices and using the Stock‐Watson (1993) procedure to correct for the correlation between the error terms and the futures prices, we find that natural gas futures are biased predictors of the corresponding future spot prices for contracts ranging from 3 to 12 months. These results cast a serious doubt on the commonly held view that natural gas futures sell at a premium over the expected future spot prices, and that this bias is due to the systematic risk of the futures price movements represented by a negative “beta.” We also find evidence for the Samuelson effect. © 2005 Wiley Periodicals, Inc. Jrl Fut Mark 25:281–308, 2005     

Forecasting equity returns: The role of commodity futures along the supply chain

This paper examines equity return predictability using the returns of commodity futures along the supply chain in China's financial market. We find that a considerable number of commodities exhibit significant in‐sample forecasting ability at the daily horizon, especially for supplier‐side equity returns. The macroeconomic risk premium effect, captured by the aggregate commodity prices, is an important source for this predictability. The out‐of‐sample results show that for most commodities, the predictability remains both statistically and economically significant, and the forecasting performance improves substantially during recessions or with economic constraints.     

The role of financial investors in determining the commodity futures risk premium

I develop and test a model to study the interaction between the commodity and stock markets. This study attempts to clarify the debate about the effect of financialization on commodity markets. Theoretically, the futures risk premium is determined by hedging pressure, stock market returns, and the commodity–equity correlation. Empirically, the effect of the stock market on the energy market became significantly greater for the futures risk premium in the period following the 2008 crisis. Furthermore, hedging pressure is a strong explanatory variable for the futures risk premium in various circumstances.     

The Relation between Physical and Risk‐neutral Cumulants

Variance swaps are natural instruments for investors taking directional bets on volatility and are often used for portfolio protection. The empirical observation on skewness research suggests that derivative professionals may also desire to hedge beyond volatility risk and there exists the need to hedge higher‐moment market risks, such as skewness and kurtosis risks. We study two derivative contracts – skewness swap and kurtosis swap – which trade the forward realized third and fourth cumulants. Using S&P 500 index options data from 1996 to 2005, we document the returns of these swap contracts, i.e., skewness risk premium and kurtosis risk premium. We find that the both skewness and kurtosis risk premiums are significantly negative.     

The forward pricing function of the shipping freight futures market

This article investigates the unbiasedness hypothesis of futures prices in the freight futures market. Being the only market whose underlying asset is a service, it sets it apart from other markets investigated so far in the literature. Cointegration techniques, employed to examine this hypothesis, indicate that futures prices one and two months before maturity are unbiased forecasts of the realized spot prices, whereas a bias exists in the three-months futures prices. This mixed evidence is in agreement with studies in other markets and suggests that the acceptance or rejection of unbiasedness depends on the idiosyncrasies of the market under investigation and on the time to maturity of the contract. Despite the existence of a bias in the three-months prices, futures prices for all maturities are found to provide forecasts of the realized spot prices that are superior to forecasts generated from error correction, ARIMA, exponential smoothing, and random walk models. Hence it appears that users of the BIFFEX market receive accurate signals from the futures prices (regarding the future course of cash prices) and can use the information generated by these prices to guide their physical market decisions. © 1999 John Wiley & Sons, Inc. Jrl Fut Mark 19: 353–376, 1999     

Information content of extended trading for index futures

The recent extension of trading hours for Hang Seng Index Futures provides an opportunity to examine whether extended futures trading contains useful information about spot returns. Using the weighted price contribution measure, we find that pre‐open futures trades are associated with significant price discovery. We extend the model from T. Hiraki, E. D. Maberly, and N. Takezawa (1995) and adjust for the existence of a pre‐open trading session and the overnight trading of cross‐listed shares in London. Our results indicate that extended trading for index futures contains useful information in explaining subsequent spot returns during the trading day. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:861–886, 2004     

中国黄金期货与现货市场的相关性及其套期保值研究

通过构建VAR-DCC-MVGARCH模型,检验2008—2011年中国黄金期货与现货市场的相关性,并分析最小化资产组合风险的最优套期保值率及其绩效,结果表明:黄金市场仅存在着现货收益率对期货收益率的单向影响;收益率的波动间具有高度正相关的时变特征;动态套期保值组合能够有效地规避黄金现货的投资风险。     

Volatility and trading demands in stock index futures

In this study we examine how volatility and the futures risk premium affect trading demands for hedging and speculation in the S&P 500 Stock Index futures contracts. To ascertain if different volatility measures matter in affecting the result, we employ three volatility estimates. Our empirical results show a positive relation between volatility and open interest for both hedgers and speculators, suggesting that an increase in volatility motivates both hedgers and speculators to engage in more trading in futures markets. However, the influence of volatility on futures trading, especially for hedging, is statistically significant only when spot volatility is used. We also find that the demand to trade by speculators is more sensitive to changes in the futures risk premium than is the demand to trade by hedgers. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:399–414, 2003