Conditional correlations in the returns on oil companies stock prices and their determinants

The identification of the forces that drive stock returns and the dynamics of their associated volatilities is a major concern in empirical economics and finance. This analysis is extremely important for determining optimal hedging strategies. This paper investigates the stock prices’ returns and their financial risk factors for several integrated oil companies, namely Bp (BP), Chevron-Texaco (CVX), Eni (ENI), Exxon-Mobil (XOM), Royal Dutch (RD) and Total-Fina Elf (TFE). We measure the actual co-risk in stock returns and their determinants “within” and “between” the different oil companies, using multivariate cointegration techniques in modelling the conditional mean, as well as multivariate GARCH models for the conditional variances. The distinguishing features of this paper are: (i) focus on the determinants of the market value of each company using the cointegrated VAR/VECM methodology; (ii) specification of the conditional variances of VECM residuals with the Constant Conditional Correlation (CCC) multivariate GARCH model of Bollerslev [(1990) Review of Economics and Statistics 72:498–505] and the Dynamic Conditional Correlation (DCC) multivariate GARCH model of Engle [(2002) Journal of Business and Economic Statistics 20:339–350]; (iii) discussion of the performance of optimal hedge ratios calculated with the DCC estimates. The “within” and “between” DCC indicate time-varying interdependence between stock return volatilities and their determinants. Moreover, DCC models are shown to produce more accurate hedging strategies.     

中国期货市场与现货市场之间的引导关系研究

利用DSEM与含有交易行为变量的VAR引导关系模型，本文分别对我国期货市场与现货市场之间的价格引导关系、波动性引导关系进行了实证研究。研究结果表明：铝、铜、橡胶和大豆期、现货价格之间均存在双向引导关系，但其期、现货价格之间的引导程度是不同的，总体而言，期货价格对现货价格均具有较强的引导作用，现货价格对期货价格的引导作用较弱；而小麦市场只存在期货价格对现货价格的引导关系。从期、现货市场之间的波动性关系而言，铝、铜、橡胶期、现货市场之间的波动性均存在双向引导关系，期货市场对现货市场的波动性引导作用均较强；大豆市场仅存在期货市场波动性对现货市场的单向引导作用：而小麦期、现货市场之间的波动性不存在任何引导关系。同时，本文从市场信息角度，系统研究了交易量和空盘量对期、现货市场的波动性的影响。     

中小景区竞争力提升研究

本文首先分析了景区竞争力的有关理论,然后结合中小景区的特征来分析制约其发展的内外部因素,在此基础上提出提升其竞争力的基本思路和对策。     

铜期货价格与现货价格的关系及启示

随着经济的快速发展,我国对大宗商品的消费需求不断增加,然而综观我国目前的对外贸易,作为大买家却没有定价权,这与需求大国和对外贸易大国的身份极不相称。本文对铜期货价格与现货价格的关系进行了实证研究,进而对现货市场价格的局限性及期货市场价格的功能进行了理性分析,提出利用期货市场争夺国际定价权。     

The component procurement problem for the loss-averse manufacturer with spot purchase

This paper studies the purchasing behaviour of a loss-averse engineer-to-order manufacturer, who purchases a key component for his final product from a supplier under a single-wholesale-price contract with spot purchase opportunities, where both the product demand and the component spot price are uncertain. Through newsvendor type of models, we analyze several key issues, including the effects of the manufacturer's loss aversion, and the effects of demand and spot price uncertainties on the manufacturer's decision behaviour. We find that the purchasing behaviour of the loss-averse manufacturer differs from those of the risk-neutral and risk-averse ones. Specifically, we identify some sufficient conditions under which the loss-averse manufacturer may purchase a larger order quantity in advance when demand becomes more uncertain or when the price becomes more uncertain. We also discuss the two-wholesale-price contract and show that fixing the emergency supply price may lead to a smaller order quantity.     

Stock index futures hedging in the emerging Malaysian market

The paper investigates hedging effectiveness of dynamic and constant models in the emerging market of Malaysia where trading information is not readily available and market liquidity is lower compared to the developed equity markets. Using daily data from December 1995 to April 2001 and bivariate GARCH(1,1) and TGARCH models, the paper uses differing variance–covariance structures to obtain hedging ratios. Performance of models is compared in terms of variance reduction and expected utility levels for the full sample period as well as the three sub-periods which encompass the Asian financial crisis and introduction of new capital control measures in Malaysia. Findings show that rankings of the hedging models change for the in-sample period depending on evaluation criteria used. TGARCH based models provide better hedging performance but only in the period of higher information asymmetry following the imposition of capital controls in Malaysia. Overall, despite the structural breaks caused by the Asian financial crisis and new capital control regulations, out of sample hedging performance of dynamic GARCH models in the Malaysian emerging market is as good as the one reported for the highly developed markets in the previous literature. The findings suggest that changes in the composition of market agents caused by large scale retreat of foreign investors following the imposition of capital control regulations do not seem to have any material impact on the volatility characteristics of the Malaysian emerging market.