原油价格与经济政策不确定性对大宗商品市场非对称冲击效应研究

利用面板分位回归模型,考量不同市场环境下原油价格与经济政策不确定性对大宗商品市场非对称性冲击效应。结果表明：油价冲击对中国大宗商品收益的影响具有非对称性,正负油价冲击对其均有促进作用,但随着市场环境好转,正油价冲击的作用逐渐增强,负油价冲击则逐渐减弱;政策不确定性对大宗商品收益有促进作用,但在牛市环境下有抑制作用;且危机前后,油价冲击对大宗商品收益的影响存在非对称性效应。     

Which form of hedging matters — Operational or financial? Evidence from the US oil and gas sector

We examine the extent and impact of operational and financial hedging on commodity price risk in US oil and gas companies. We find significant exposure to underlying commodity movements. Using a combination of hand collected and publicly available data we examine the impact of hedging strategies. We find no evidence that operational hedging, defined here as multinationality, is effective. In contrast, we find that financial hedging is significant and impactful. Sub-period analysis shows that the effectiveness of financial hedging diminishes when commodity price volatility is high.     

Effects of speculation and interest rates in a “carry trade” model of commodity prices

The paper presents and estimates a model of the prices of oil and other storable commodities, a model that can be characterized as reflecting the carry trade. It focuses on speculative factors, here defined as the trade-off between interest rates on the one hand and market participants' expectations of future price changes on the other hand. It goes beyond past research by bringing to bear new data sources: survey data to measure expectations of future changes in commodity prices and options data to measure perceptions of risk. Some evidence is found of a negative effect of interest rates on the demand for inventories and thereby on commodity prices and positive effects of expected future price gains on inventory demand and thereby on today's commodity prices.     

Oil commodity returns and macroeconomic factors: A time-varying approach

This paper analyses the dynamic influence of macroeconomic factors on oil commodity returns (crude oil and heating oil) shown in monthly data over the period of 1990–2013. Using a time-varying parameter model via the Kalman filter, we find that macroeconomic factors are relevant for explaining oil commodity returns. We find that multilateral exchange rates have a negative effect on commodity returns. We confirm the existence of a strong linkage between energy and non-energy commodities. More importantly, we find shifts in global demand and SP500 effects that are not identified through the constant parameter model. These variables have had a progressively positive effect on oil commodity returns, especially since 2008.     

Evidences for a structural change in the oil market before a financial crisis: The flat horizon effect

There are growing evidences that the commodity bubble in the 2000s had a major impact in the 2007–08 financial crisis. A salient feature of this commodity bubble was the dramatic increasing in the correlation of indexed commodities with oil price following the financialisation of the oil market. In this paper we suggest that, besides the growing demand from emerging economies and the following inflow of money from speculative traders, the introduction of the electronic platform could have had an important and underestimated effect on the oil market. Our analysis of the spot and futures oil prices at the NYMEX based on the Generalized Hurst Exponent confirms that the period 2004–2007 is pivotal in the oil market and corroborates the hypothesis that a structural change occurred in both markets. The evident decrease in multifractality suggests a flattening of the time horizon in financial oil markets and the coexistence of long-termism and short-termism. This structural change could partially explain the observed increase of correlations between commodities and oil price.     

The Relationship Between Energy Commodity Prices and Electricity and Market Index Performances: Evidence from an Emerging Market

We investigate the effect of energy commodity price movements on market and electricity index returns in Turkey for the periods before, during, and after the year 2008. Although the Turkish economy is highly reliant on oil, we find that oil price does not lead either electricity or market indexes. This might be attributable to sluggish integration of financial markets in Turkey compared to developed markets. Natural gas price leads electricity index in the pre-2008 period. Its significance is reduced following the decline in natural gas usage in electricity production. This suggests that commodity dependence may be driving the link between commodity and asset prices in related sectors.     

Learning and price volatility in duopoly models of resource depletion

The combination of learning and depletion in non-renewable resource markets adds significant volatility to commodity prices. The market consists of a small number of suppliers who make depletion plans based on their perceptions of how sensitive price is to supply. Learning leads to changes in these perceptions and hence the revision of depletion plans, which can have a dramatic effect on market supply and price. Firstly, price trends upwards faster than the rate of time preference as the non-renewable resource approaches exhaustion. Secondly, there are frequent escape episodes in which price rises rapidly before gradually falling back. The striking volatility and nonstationarity in commodity prices that results has parallels in oil price data.     

Long term spread option valuation and hedging

This paper investigates the valuation and hedging of spread options on two commodity prices which in the long run are in dynamic equilibrium (i.e., cointegrated). The spread exhibits properties different from its two underlying commodity prices and should therefore be modelled directly. This approach offers significant advantages relative to the traditional two price methods since the correlation between two asset returns is notoriously hard to model. In this paper, we propose a two factor model for the spot spread and develop pricing and hedging formulae for options on spot and futures spreads. Two examples of spreads in energy markets – the crack spread between heating oil and WTI crude oil and the location spread between Brent blend and WTI crude oil – are analyzed to illustrate the results.     

Demand effects and speculation in oil markets: Theory and evidence

We present evidence showing the existence of stable cointegrating vectors connecting four important variables in the U.S. and global oil markets: oil production, stocks of crude oil, the real price of oil, and broad measures of income. Our data are monthly, and go back to the 1930s, split into sub-samples which correspond to periods before and after the 1973 crisis. We further show that the cointegrating vectors found in the data accord well with an extended commodity storage model which allows for demand growth dynamics and for supply regimes. Specifically, inventories and price move in opposite directions when supply is flexible, but the relationship reverses so that they comove when supply is inflexible.     

信息传导与市场整合——基于商品期货上市的准自然实验

从制度设计上打破市场分割、促进市场整合,对提高市场效率、促进经济有序健康发展具有重要意义。本文以商品期货上市作为准自然实验,构建双重差分模型,实证检验了商品期货上市交易对现货商品市场价格整合的影响。研究发现,现货商品市场价格整合程度在相应商品期货上市后显著提升,这是因为商品期货上市显著地促进了价格信息在全国范围内的传导,且这种提升效应主要体现在价格信息传导比较顺畅的地区。此外,商品期货上市提高了现货商品市场价格同步性,缓解了现货商品价格信息滞后程度,降低了现货商品交易成本。进一步研究发现,商品期货市场的交易信息质量越高,越有利于提高现货商品市场的整合程度。本研究为当前我国建设全国统一大市场提供了一定参考。     

去伪存真:油价趋势与股票市场——来自“一带一路”35国的经验证据

油价波动深刻影响全球经济,严重时会造成全球股市动荡,甚至引发系统性金融风险。然而油价中的信息噪音严重阻碍国际油价对股票市场的预测效果。本文提出的移动平均法可有效减弱信息噪音,研究表明,本文基于移动平均法构建的油价趋势因子对“一带一路”沿线国家股票市场具有良好的样本内和样本外可预测性。进一步研究发现,国际油价波动对产油国和非产油国股票市场的影响存在非对称性。本文为国际油价冲击股票市场提供了新的有力证据,同时本文研究成果提示了油价风险,对维持我国股票市场稳定,保持金融稳定具有一定意义。     

Regulatory reform and market efficiency: The case of Indian agricultural commodity futures markets

We present the results of two efficiency measures that include intraday return predictability measure based on order imbalance and measures of several variance ratio tests on intraday subsamples of nine major Indian agricultural commodity futures (castor seed, cotton oil cake, rape mustard seed, soybean, refined soya oil, crude palm oil, jeera, chana, and turmeric) quoted in the National Commodity and Derivatives Exchange (NCDEX). We perform the efficiency measures on five subsamples with holding periods of 5, 10, 15, 30, and 60 min over two sample periods following the announcement of the merger between the Forward Market Commission (FMC) and Securities Exchange Board of India (SEBI). We compare results of tests of weak-form market efficiency of futures markets between two periods (pre-merger period and post-merger period). Our results confirm that Indian agricultural commodity futures markets continue to remain inefficient in the short-term during both pre-merger and post-merger periods. Based on these findings, it is likely that profitable trading strategies in the short intraday intervals will be available for traders and market participants during post-merger period. Thus, regulators must focus more on policy initiative so as to enhance market quality in order to address such inefficiencies in Indian commodity futures markets.     

国际金融市场与国际原油期货市场溢出效应实证检验——基于VAR-BEKK模型的分析

文章通过构建VAR模型和BEKK模型对道琼斯股票市场、美元/欧元汇率市场与国际原油期货市场的动态关系进行了实证检验。结果表明：道琼斯股票市场与WTI原油期货市场存在双向的价格溢出效应,以及前者向后者的单向波动溢出效应;美元/欧元汇率市场存在向WTI原油期货市场单向的价格溢出效应和波动溢出效应。所以,国际原油期货市场与国际金融市场联系紧密,国际原油的金融属性日益体现,其价格变动更多受外部国际金融市场风险影响。     

The historic oil price fluctuation during the Covid-19 pandemic: What are the causes?

On 20 April 2020, the West Texas Intermediate (WTI) crude oil price dropped to negative levels for the first time in history. This study examines the factors underlying the historic oil price fluctuation during the Covid-19 pandemic. The autoregressive distributed lag (ARDL) bounds testing approach incorporating a structural break is applied to the daily series from 17 January to 14 September 2020 to analyze long-run relationships and short-run dynamics. The results reveal that increases in Covid-19 pandemic cases, US economic policy uncertainty, and expected stock market volatility contributed to the fall in the WTI crude oil price, whereas the fall in the global stock markets appears to significantly reduce the fall. Furthermore, the Russia–Saudi Arabia oil price war and speculation on oil futures are shown to play a critical part in the collapse of the oil markets. The findings are consistent with our expectations. Although it is reasonable to assume that the solution to this oil crisis is a pick-up in global oil demand, which will occur only when the novel coronavirus is defeated, this study proposes policy recommendations to cope with the current oil price crash.     

Predictability of structural co-movement in commodity prices: the role of technical indicators

This paper investigates the financialization and structural co-movement of several commodity futures using factor variance decomposition and predictability of technical indicators and macro variables. We find that financialization is still a dominant player in the commodity market and that recent commodity price fluctuations can be significantly and robustly forecasted by technical analyses of commodity index investments. Moreover, the co-movement of commodities is demonstrated by variance decomposition and explained as commodity index investment, which provides evidence of financialization. The overall empirical analysis reveals that technical indicators and macro variables can statistically and economically forecast the indexed investment and off-index trading, respectively, which indicates that they are suitable predictors of the commodity markets.     

Selective hedging strategies for crude oil futures based on market state expectations

This paper studies the ex-ante selective hedging strategies of crude oil futures contracts based on market state expectations and compares the hedging performances to the traditional minimum variance routine hedging strategies. The main advantage of the proposed method is that it achieves a trade-off between return and risk, rather than hedges risk at all costs. Specifically, we first use a multi-input Hidden Markov Model(HMM) to identify the market state, assess the market’s herding impact, and then integrate the findings of identification and measurement to forecast the price trend. We offer an adjustment criterion for the hedge ratios driven by GARCH²-type models based on the anticipated market state. We conducted an empirical analysis to examine the hedging effect of WTI and Brent crude oil futures, the results indicate that the proposed state-dependent hedging strategies are superior to the traditional model-driven hedging strategies concerning the hedged portfolio based on four criteria. The robustness check reveals that the proposed hedging strategies still outperform in different market situation. The findings can help traders in the crude oil markets, and the methodology can be applied to other energy markets.     

Does global liquidity drive commodity prices?

This paper tackles the question of whether a cross-sectional perspective on monetary policy is capable of explaining movements in global commodity prices. In this vein, we contribute to the rich literature on global liquidity in two different ways: on the one hand, to achieve a global series in terms of common monetary policy shocks, we propose a distinction between common and idiosyncratic factors across economies, as proposed by Bai and Ng (2004). Our second innovation stems from the consideration of a Markov-switching vector error correction model when analyzing time-varying short-run dynamics. Having identified the long-run structure which includes a proportional relationship between commodity prices and global liquidity in the first step, our results indeed show that the impact of a global liquidity measure on different commodity prices is significant and varies over time. One regime approximately accounts for times where commodity prices significantly adjust to disequilibria, while the second regime is characterized by either a weak or no commodity price adjustment. The fact that global liquidity also reacts to disequilibria in a specific regime demonstrates the two-way causality between monetary policy and commodity prices.     

Does the stock market drive herd behavior in commodity futures markets?

This paper contributes to the debate on commodity financialization by extending tests of herd behavior to commodity futures markets. Utilizing a regime-switching model, we test the presence of herd behavior in a number of commodity sectors including energy, metals, grains and livestock during the low and high market volatility states. We find significant evidence of herd behavior in grains only during the high volatility state. We also find that large price movements in the energy and metal sectors significantly contribute to herd behavior in the market for grains. Finally, we find no significant effect of the stock market on herd behavior in the commodity futures market. Our findings in general do not support the much debated commodity financialization hypothesis.     

石油价格变动对价格总水平的影响分析

石油是最重要的战略资源之一,其价格变动对价格总水平和经济运行有着重要的影响。本文在阐述石油价格变动影响价格总水平的机理和途径的基础上,从投入产出的角度分析石油价格变动对各产业产品价格及价格总水平的具体影响,并通过分析石油价格与价格总水平变动的历史规律来进一步探讨二者之间影响的数量关系。     

Oil Price and Stock Market Synchronization in Gulf Cooperation Council Countries

Knowing that the Gulf Cooperation Council (GCC) economies are dichotomous in nature, and growth in the non-oil sector is tributary to the oil sector, we document the extent of synchronization between crude oil prices and stock markets for each of the GCC markets and for the GCC as an economic bloc. We use both the bivariate and multivariate nonparametric synchronicity measures proposed by Mink et al. (2007) to assess that linkage. We find a low to mild (mild to strong) degree of synchronization between oil price and stock market returns (volatilities). In a very few instances, we find very strong (above 80 percent) associations between these variables. These results hold irrespective of whether we assume that stock market participants form adaptive or rational expectations about the price of oil. Dynamic factor results confirm that shocks to volatility are more important than shocks to oil price returns for the GCC stock markets.