Morema Kgotso, Bonga-Bonga Lumengo
University of Johannesburg, South Africa.
Resour Policy. 2020 Oct;68:101740. doi: 10.1016/j.resourpol.2020.101740. Epub 2020 Jun 17.
This paper assesses the impact of gold and oil price fluctuations on the volatility of the South African stock market and its component indices or sectors - namely, the financial, industrial and resource sectors - to infer the link between the commodity and stock markets in South Africa. Use is made of the vector autoregressive asymmetric dynamic conditional correlation generalised autoregressive conditional heteroskedasticity (VAR-ADCC-GARCH) model to this end. Moreover, the paper assesses the magnitude of the optimal portfolio weight, hedge ratio and hedge effectiveness for portfolios constituted of a pair of assets, namely oil-stock and gold-stock pairs. The findings of the study show that there is significant volatility spillover between the gold and stock markets, and the oil and stock markets. This finding suggests the importance of the link between the commodity and stock markets, which is essential for portfolio management. With reference to portfolio optimization and the possibility of hedging when using the pairs of assets under study, the findings suggest the importance of combining gold and stocks as the best strategy to hedge against stocks risk, especially during financial crises.
本文评估黄金和石油价格波动对南非股票市场及其成分指数或板块(即金融、工业和资源板块)波动性的影响,以推断南非商品市场与股票市场之间的联系。为此,使用了向量自回归非对称动态条件相关广义自回归条件异方差(VAR - ADCC - GARCH)模型。此外,本文评估了由一对资产(即石油 - 股票对和黄金 - 股票对)构成的投资组合的最优投资组合权重、套期保值比率和套期保值有效性的大小。研究结果表明,黄金市场与股票市场之间以及石油市场与股票市场之间存在显著的波动溢出效应。这一发现表明商品市场与股票市场之间联系的重要性,这对投资组合管理至关重要。关于投资组合优化以及使用所研究的资产对进行套期保值的可能性,研究结果表明,将黄金和股票结合起来作为对冲股票风险的最佳策略非常重要,尤其是在金融危机期间。