Amewu Godfred, Owusu Junior Peterson, Amenyitor Elvis Aaron
Department of Finance, School of Business, University of Ghana, Legon, Ghana.
Department of Finance, School of Business, University of Cape Coast, Ghana.
Sci Afr. 2022 Jul;16:e01146. doi: 10.1016/j.sciaf.2022.e01146. Epub 2022 Mar 15.
This paper probes deeper into the co-movement of Ghana's equity index and exchange rate with international equity markets and further determine whether these co-movements are driven by global uncertainties. Also, we sought to determine how the COVID-19 pandemic alters the dynamics of these relationships. We employ the wavelet technique to data from January 19, 2012 to March 1, 2021 to the split between pre-COVID-19 and COVID-19 periods. The results reveal that the dynamics of co-movement or interconnectedness of exchange rate and Ghana Stock Exchange composite index has evolved over time and across frequencies. Besides, the cone of influence, as shown by the wavelet spectrum, does not cover the entire data frequency which suggests that long-term forecast of exchange rate and equity index in Ghana beyond four years could be misleading since significant levels of interdependences are concentrated around the mid-team scales. In addition, we found evidence to support low-medium term lead-lag connections between exchange rate and Ghana Stock Exchange Composite Index in 2013 to 2014 and 2016. Further, the co-movement between exchange rate or Ghana Stock Exchange Composite Index and international equity markets show similarly weak association at all scales. A closer scan of the interdependencies among these variables are more intense during COVID-19 than during the pre-COVID-19 period. Finally, we observe a strong co-movement between the rise in COVID-19 cases and exchange rate at higher frequency scales where exchange rate lags Ghana's equity index and they are out-of-phase.
本文深入探究了加纳股票指数和汇率与国际股票市场的共同变动情况,并进一步确定这些共同变动是否由全球不确定性因素驱动。此外,我们试图确定新冠疫情如何改变这些关系的动态变化。我们运用小波技术对2012年1月19日至2021年3月1日的数据进行分析,以区分新冠疫情前和新冠疫情期间。结果显示,汇率与加纳证券交易所综合指数的共同变动或相互关联动态随时间和频率发生了演变。此外,小波谱显示的影响锥并未覆盖整个数据频率,这表明对加纳汇率和股票指数超过四年的长期预测可能会产生误导,因为显著的相互依存水平集中在中期尺度附近。此外,我们发现有证据支持2013年至2014年以及2016年期间汇率与加纳证券交易所综合指数之间存在中短期的领先-滞后关系。此外,汇率或加纳证券交易所综合指数与国际股票市场之间的共同变动在所有尺度上均呈现出类似的弱关联。对这些变量之间相互依存关系的更仔细审视表明,新冠疫情期间的相互依存程度比新冠疫情前更为强烈。最后,我们观察到在高频尺度上,新冠疫情病例增加与汇率之间存在强烈的共同变动,此时汇率滞后于加纳股票指数,且二者不同步。