Panazan Oana, Gheorghe Catalin
Department of Engineering and Industrial Management, Transilvania University of Brasov, Brasov, Romania.
PLoS One. 2025 Feb 21;20(2):e0312155. doi: 10.1371/journal.pone.0312155. eCollection 2025.
This study conducts a comparative analysis of how geopolitical risk (GPR) and innovation impact stock returns in the defense industry based on data from 75 defense companies across 17 countries and 4 continents. With daily datasets spanning from January 1, 2014 to March 29, 2024, wavelet coherence and wavelet phase differences were used to conduct the analysis. The results revealed that innovation had a greater and more pronounced impact during the entire analysis period compared with the influence of GPR events. GPRs exerted an uneven and heterogeneous impact on global defense stocks and had a concentrated impact during events that generated uncertainty. Overall, we found significant time-varying dependence across a large number of companies at different time frequencies. The COVID-19 pandemic did not have a major impact on companies in the defense industry. Further, GPR events led to increased volatility during the Russia-Ukraine war, leading to increased uncertainty. In addition to the dominant role they play in the world defense market, US companies served as a robust hedge, especially from 2021 to 2022. Defense companies in the UK are more sensitive to both GPR events and innovation, followed by companies in Germany and France. Comparative analysis of the scalograms of China reveals a greater influence of innovation compared with GPR events. Thus, diversification opportunities have been extended from the defense industry in China, offering investors a promising way to capitalize on refuge opportunities during periods of disruption. To mitigate the global rearmament trend, we suggest alternative investment opportunities for different time horizons.
本研究基于来自4大洲17个国家的75家国防公司的数据,对地缘政治风险(GPR)和创新如何影响国防工业的股票回报进行了比较分析。利用2014年1月1日至2024年3月29日的每日数据集,采用小波相干和小波相位差进行分析。结果显示,在整个分析期内,与GPR事件的影响相比,创新的影响更大且更显著。GPR对全球国防股的影响不均衡且具有异质性,在产生不确定性的事件期间有集中影响。总体而言,我们发现在不同时间频率下,大量公司之间存在显著的时变依赖性。新冠疫情对国防工业的公司没有重大影响。此外,GPR事件在俄乌战争期间导致波动性增加,进而导致不确定性增加。除了在世界国防市场中发挥的主导作用外,美国公司起到了强大的避险作用,尤其是在2021年至2022年期间。英国的国防公司对GPR事件和创新都更敏感,其次是德国和法国的公司。对中国的小波图进行比较分析发现,与GPR事件相比,创新的影响更大。因此,中国国防工业的多元化机会得到了扩展,为投资者在动荡时期利用避险机会提供了一条有前景的途径。为缓解全球重新武装化趋势,我们针对不同的时间跨度提出了替代投资机会。