In this paper, we adopt multifractal detrended fluctuation analysis (MF-DFA) to explore relationships between the Russia–Ukraine conflict and defense stock markets. Specifically, we analyze the behaviors of 20 U.S. defense stock markets confronting with the Russia–Ukraine conflict. By using the stock price charts, combined with multifractal spectra and singularity exponents calculated by MF-DFA, we explore how the conflict affects the defense stock markets in perspectives of closing price, market efficiency and stability. In addition, the obtained results reveal high level of consistency while each type shows distinct features. According to singularity exponents, we observe that all 20 stocks can be divided into three types which we note as $Types$ A, B and C. We infer from the singularity spectra that the $Type$ A stock price will experience plummet after the conflict, instead, stock price of $Type$ A increases based on stock price charts, while stock price of $Types$ B and C rises as predicted. For $Type$ A stocks, their market efficiency and stability show increments where we draw completely opposite conclusion for $Type$ B stocks. Furthermore, we also note that $Type$ C stocks include two defense stocks having a special phenomenon, and their multifractal spectra indicate the increase in stock price which behave like $Type$ B stocks. However, their singularity exponents reduce during the conflict, meaning the slump in their market efficiency, which share the same characteristic as $Type$ A stocks. Hence, we treat $Type$ C stocks as a unique type. To mitigate the influence of stochastic elements in the experimental process, three comparative analyses are undertaken. We humbly believe that the induced implications are aroused by the Russia–Ukraine conflict.

在本文中，我们采用多重分形去趋势波动分析（MF-DFA）来探讨俄罗斯-乌克兰冲突与国防股票市场之间的关系。具体来说，我们分析了 20 个美国国防股票市场在俄罗斯-乌克兰冲突面前的表现。通过利用股价图表，结合多重分形谱和MF-DFA计算的奇异指数，我们从收盘价、市场效率和稳定性的角度探讨了冲突如何影响国防股票市场。此外，所获得的结果显示出高度的一致性，而每种类型都显示出不同的特征。根据奇点指数，我们观察到所有 20 只股票可以分为三种类型，我们记为$\mathrm{时间}ypes$ 甲、乙、丙。我们从奇点谱推断出$\mathrm{时间}ype$ 冲突后股价会暴跌，相反，$\mathrm{时间}ype$ A根据股价图表上涨，而股价$\mathrm{时间}ypes$ B和C如预期上升。为了$\mathrm{时间}ype$ A股的市场效率和稳定性呈现增量，我们得出完全相反的结论$\mathrm{时间}ype$ B股。此外，我们还注意到$\mathrm{时间}ype$ C股包括两只具有特殊现象的国防股，它们的多重分形谱表明股价上涨，其表现如下$\mathrm{时间}ype$ B股。然而，它们的奇点指数在冲突期间降低，这意味着它们的市场效率下降，这与$\mathrm{时间}ype$ A股。因此，我们对待$\mathrm{时间}ype$ C股作为一种独特的类型。为了减轻实验过程中随机因素的影响，进行了三种比较分析。我们谦虚地认为，这种影响是由俄罗斯和乌克兰冲突引起的。