中国大宗商品期货市场定价机制研究

大宗商品期货市场是我国资本市场的重要组成部分,其定价有效性关系到投资者套期保值和价格发现等功能的实现。本文对国际前沿研究中常用的定价因子进行全面系统梳理,并对这些因子对我国商品期货合约收益率的解释和预测能力进行检验。在此基础上,本文构建了适用于我国大宗商品期货市场的包含市场、基差以及基差动量的三因子定价模型。进一步研究表明,基于大宗商品存储理论和现货存货数据构建的投资组合收益率可以被本文三因子模型有效解释,验证了经典的存储理论在我国的适用性。此外,本文对基差与基差动量两个重要因子的经济学意义进行了阐释。本文研究为进一步厘清大宗商品期货市场定价机制提供了一定参考。     

A Tale of Two Premiums: The Role of Hedgers and Speculators in Commodity Futures Markets

This paper studies the dynamic interaction between the net positions of traders and risk premiums in commodity futures markets. Short-term position changes are driven mainly by the liquidity demands of noncommercial traders, while long-term variation is driven primarily by the hedging demands of commercial traders. These two components influence expected futures returns with opposite signs. The gains from providing liquidity by commercials largely offset the premium they pay for obtaining price insurance.     

Capturing the risk premium of commodity futures: The role of hedging pressure

We construct long–short factor mimicking portfolios that capture the hedging pressure risk premium of commodity futures. We consider single sorts based on the open interests of hedgers or speculators, as well as double sorts based on both positions. The long–short hedging pressure portfolios are priced cross-sectionally and present Sharpe ratios that systematically exceed those of long-only benchmarks. Further tests show that the hedging pressure risk premiums rise with the volatility of commodity futures markets and that the predictive power of hedging pressure over cross-sectional commodity futures returns is different from the previously documented forecasting power of past returns and the slope of the term structure.     

Default Premiums in Commodity Markets: Theory and Evidence

We model the effect of nonperformance risk on forward and futures pricing and look for evidence of nonperformance risk in precious metals futures prices from the “Hunt Brothers”episode. Changes in default premiums are measured and related to the sequence of events in the metals markets during this period. Results suggest first that ex ante costs of nonperformance can be a significant, priced factor in commodity markets and second that the arrival of new information is often associated with changes in these costs. The evidence has implications for both theoretical and empirical research on commodity markets.     

Beyond Basis Basics: Liquidity Demand and Deviations from the Law of One Price

Deviations from the law of one price between futures and spot prices—the futures-cash basis—capture information about liquidity demand for equity market exposure in global markets. We show that the basis comoves with dealer and investor futures positions, is contemporaneously positively correlated with futures and spot market returns, and negatively predicts futures and spot returns. These findings are consistent with the futures-cash basis reflecting liquidity demand that is common to futures and cash equity markets. We find persistent supply-demand imbalances for equity index exposure reflected in the basis, giving rise to an annual premium of 5% to 6%.     

Liquidity commonality in commodities

We examine liquidity commonality in commodity futures markets. Using data from 16 agricultural, energy, industrial metal, precious metal, and livestock commodities, we show there is a strong systematic liquidity factor in commodities. Liquidity commonality was present in 1997–2003 when commodity prices were relatively stable and during the recent boom. There is some support for both “supply-side” and “demand-side” explanations for this commonality. We find no evidence of a consistent link between stock and commodity liquidity in general. Energy commodities appear to provide a better hedge against equity market liquidity risk than the other commodity families.     

Return and volatility co-movement in commodity futures markets: the effects of liquidity risk

Commodity markets are a widely researched topic in the field of finance. In this paper, we investigate the co-movement of return and volatility measures in different commodity futures markets and how these measures are affected by liquidity risk. First, we find that commodity returns display co-movement and that liquidity risk plays a key role in shaping asset return patterns. Moreover, we show that the volatilities of commodity returns co-move, and we demonstrate the role of liquidity risk in this joint pattern. We also find that the commodity markets we investigated share a common volatility factor that determines their joint volatility co-movement. Because liquidity risk affects both commodity returns and volatility shocks, it might be interpreted as the common causal factor driving both measures simultaneously. Therefore, we affirm the view that liquidity shocks are firmly related to two residual risks originating from both market return and market volatility. Finally, we also show that liquidity spillovers can significantly drive cross-sectional correlation dynamics.     

Time series momentum

We document significant “time series momentum” in equity index, currency, commodity, and bond futures for each of the 58 liquid instruments we consider. We find persistence in returns for one to 12 months that partially reverses over longer horizons, consistent with sentiment theories of initial under-reaction and delayed over-reaction. A diversified portfolio of time series momentum strategies across all asset classes delivers substantial abnormal returns with little exposure to standard asset pricing factors and performs best during extreme markets. Examining the trading activities of speculators and hedgers, we find that speculators profit from time series momentum at the expense of hedgers.     

An Anatomy of Commodity Futures Risk Premia

We identify two types of risk premia in commodity futures returns: spot premia related to the risk in the underlying commodity, and term premia related to changes in the basis. Sorting on forecasting variables such as the futures basis, return momentum, volatility, inflation, hedging pressure, and liquidity results in sizable spot premia between 5% and 14% per annum and term premia between 1% and 3% per annum. We show that a single factor, the high‐minus‐low portfolio from basis sorts, explains the cross‐section of spot premia. Two additional basis factors are needed to explain the term premia.     

Comoment risk and stock returns

We estimate investable comoment equity risk premiums for the US markets. The stock's contribution to the asymmetry and the fat tails of the market portfolio's payoff are priced into a coskewness premium and a cokurtosis premium. We construct zero-investment strategies that are long and short in coskewness and cokurtosis equity risks; we infer from the spread the returns attached to a unit exposure to US equity coskewness and cokurtosis. The coskewness and cokurtosis premiums present positive monthly average returns of 0.27% and 0.14% from January 1959 to December 2011. Comoment risks appear to be significantly priced within the US stock market and display significant explanatory power regarding the US size and book-to-market effects. The premiums do not subsume, but rather complement the empirical capital asset pricing model. Our analysis relies on data collected from CRSP (Chicago Research Center for Security Prices) over December 1955 to December 2011. To our knowledge, the paper is the first to propose investable higher-moment risk factors over such an extensive time period.     

Liquidity and CDS premiums on European companies around the Subprime crisis

This paper sheds new light on the liquidity dynamics of the credit default swaps (CDS) market in Europe around the Subprime crisis. Based on an original dataset of 94 European companies from 2005 to 2009, we use a panel regression analysis to study the relationship between CDS premiums and liquidity. We measure the level of liquidity, look at liquidity risk, and study the liquidity spillovers from the bond and equity markets to the CDS market. We show that the effect of liquidity on CDS premiums is dominated by the influence of worsening credit conditions and deteriorating investors?? expectations about default risk. Controlling for credit risk, we also find that liquidity risk is priced in the European CDS market and that liquidity spillovers from the bond market matter in determining CDS premiums.     

Municipal Debt and Marginal Tax Rates: Is There a Tax Premium in Asset Prices?

We study the marginal tax rate incorporated into short‐term municipal rates using municipal swap market data. Using an affine model, we identify the marginal tax rate and the credit/liquidity spread in 1‐week tax‐exempt rates, as well as their associated risk premia. The marginal tax rate averages 38.0% and is related to stock, bond, and commodity returns. The tax risk premium is negative, consistent with the strong countercyclical nature of after‐tax fixed‐income cash flows. These results demonstrate that tax risk is a systematic asset pricing factor and help resolve the muni‐bond puzzle.     

Is idiosyncratic asymmetry priced in commodity futures?

In this article, we use a recently introduced asymmetry measure, IE, to measure the idiosyncratic asymmetry of commodity futures returns and find that idiosyncratic asymmetry negatively and significantly predicts commodity futures returns cross sectionally. Furthermore, we find that a long–short trading strategy based on idiosyncratic asymmetry generates significant abnormal returns, which cannot be explained by traditional risk factors in commodity futures and persists up to 12 months. Moreover, idiosyncratic asymmetry appears to be a priced factor in commodity futures with significant risk premium. Finally, we confirm that IE is better at capturing the pricing effect of idiosyncratic asymmetry than the traditional skewness measure.     

Variance risk in commodity markets

We analyze the variance risk of commodity markets. We construct synthetic variance swaps and find significantly negative realized variance swap payoffs in most markets. We find evidence of commonalities among the realized payoffs of commodity variance swaps. We also document comovements between the realized payoffs of commodity, equity and bond variance swaps. Similar results hold for expected variance swap payoffs. Furthermore, we show that both realized and expected commodity variance swap payoffs are distinct from the realized and expected commodity futures returns, indicating that variance risk is unspanned by commodity futures.     

Spanish Treasury bond market liquidity and volatility pre- and post-European Monetary Union

Spain enacted a number of important debt management initiatives in 1997 to prepare its Treasury bond market for European Monetary Union. We interpret the impacts of these changes through shifts in a bond liquidity “life cycle” function. Furthermore, we highlight the importance of expected average future liquidity in explaining Spanish bond liquidity premiums. We also uncover pricing biases that support the Spanish Treasury’s tactical decision to target high-coupon, premium bonds in its pre-EMU debt exchanges. Finally, we show that EMU has been associated with both a decrease in bond yield volatility and an increase in pricing efficiency.     

商品期货投资收益问题研究

按照持有期货合约的部位,将商品期货交易者细分为：标的商品生产商、加工商和投机者。在满足终期效用最大化的条件下,通过联立商品期货、现货和证券市场,推导出一个商品期货投资收益模型,证明了商品期货投资收益由期货市场的系统性风险溢价和非系统性风险溢价两部分组成,并解释了“持有期成本套利”、“现货一期货溢价”和“资本资产定价”三种理论适用于确定商品期货投资收益的前提条件。根据国内商品期货市场与证券市场之间存在负相关性的实证结论,说明发展商品基金、减少证券一商品期货市场跨市场投资的交易成本等措施有利于我国资本市场的发展和完善。     

Conventional and downside CAPM: The case of London stock exchange

Many studies on asset pricing have highlighted the importance of downside risk, in line with the actual losses of investors. In addition, the capital asset pricing model (CAPM), although presented as a universal theory, may provide significantly different rates of return in bull and bear markets. Using the CAPM under different conditions could be regarded as an alternative measurement and valuation approach to downside risk. This paper investigates conventional and downside approaches to risk taking into account different measures of downside beta coefficients. A further contribution of this research is the development of an alternative approach to testing the CAPM relationship. For this purpose, conditional relationships of the CAPM are proposed in which risk premiums are set separately in bull and bear periods. Using equity data and portfolios from the United Kingdom, we obtained positive and statistically significant downside risk premiums. We observed a slight advantage of downside measures over conventional beta measures. Conditional models provide evidence of a positive risk premium in rising markets and a negative risk premium in falling markets. The robustness analysis in subperiods indicates that these findings are largely unchanged for downside beta coefficients, which is not fulfilled by the model in a variance approach.     

Liquidity,default, taxes,and yields on municipal bonds

We examine the effects of liquidity, default and personal taxes on the relative yields of Treasuries and municipals using a generalized model with liquidity risk. The municipal yield model includes liquidity as a state factor. Using a unique transaction dataset, we estimate the liquidity risk of municipals and its effect on bond yields. Empirical evidence shows that municipal bond yields are strongly affected by all three factors. The effects of default and liquidity risk on municipal yields increase with maturity and credit risk. Liquidity premium accounts for about 9–13% of municipal yields for AAA bonds, 9–15% for AA/A bonds and 8–19% for BBB bonds. A substantial portion of the maturity spread between long- and short-maturity municipal bonds is attributed to the liquidity premium. Ignoring the liquidity risk effect thus results in a severe underestimation of municipal bond yields. Conditional on the effects of default and liquidity risk, we obtain implicit tax rates very close to the statutory tax rates of high-income individuals and institutional investors. Furthermore, these implicit income tax rates are quite stable across bonds of different maturities. Results show that including liquidity risk in the municipal bond pricing model helps explain the muni puzzle.     

Private Equity Performance and Liquidity Risk

Private equity has traditionally been thought to provide diversification benefits. However, these benefits may be lower than anticipated as we find that private equity suffers from significant exposure to the same liquidity risk factor as public equity and other alternative asset classes. The unconditional liquidity risk premium is about 3% annually and, in a four‐factor model, the inclusion of this liquidity risk premium reduces alpha to zero. In addition, we provide evidence that the link between private equity returns and overall market liquidity occurs via a funding liquidity channel.     

Systematic risk, hedging pressure, and risk premiums in futures markets

I examine the uniformity of risk pricing in futures and assetmarkets. Tests against a general alternative do not reflectcomplete integration of futures and asset markets. As predicted,estimates of the 'zero-beta' rate for futures are close to zero,and premiums for systematic risk do not differ significantlyacross assets and futures. There is, however, evidence consistentwith a specific alternative model presented by Hirshleifer (1988).Returns in foreign currency and agricultural futures vary withthe net holdings of hedgers, after controlling for systematicrisk. These results imply a degree of market segmentation andsupport hedging pressure as a determinant of futures premiums.