论文标题
在RIA-EVT-COPULA框架中预测尾巴事件
Predicting tail events in a RIA-EVT-Copula framework
论文作者
论文摘要
预测尾巴事件的发生在金融风险管理中至关重要。通过采用阈值峰值(POT)来识别财务极端的方法,我们对这些极端进行了复发间隔分析(RIA)。我们发现,连续极端(复发间隔)之间的等待时间遵循$ q $ - 指数分布,极端的大小高于阈值(超过大小),符合广义的帕累托分布。我们还发现,复发间隔与超过大小之间存在显着相关性。因此,我们通过将两个相应的边缘分布与弗兰克和AMH Copula函数连接起来,对复发间隔的联合分布进行建模,并超过大小,并应用此联合分布以估算自$ t $ t $ t $ time以前的危险概率,以在$ΔT$中观察另一个极端。此外,通过将决策算法应用于危险概率,提出了基于RIA-EVT-COPULA的极端预测模型。样本中和样本外测试都表明,这个新的极端预测框架在预测中具有更好的性能,与仅根据复发间隔的分布估计的危险概率进行比较。我们的结果不仅阐明了了解金融市场中极端发生的发生模式的新启示,而且还提高了预测风险管理财务极端的准确性。
Predicting the occurrence of tail events is of great importance in financial risk management. By employing the method of peak-over-threshold (POT) to identify the financial extremes, we perform a recurrence interval analysis (RIA) on these extremes. We find that the waiting time between consecutive extremes (recurrence interval) follow a $q$-exponential distribution and the sizes of extremes above the thresholds (exceeding size) conform to a generalized Pareto distribution. We also find that there is a significant correlation between recurrence intervals and exceeding sizes. We thus model the joint distribution of recurrence intervals and exceeding sizes through connecting the two corresponding marginal distributions with the Frank and AMH copula functions, and apply this joint distribution to estimate the hazard probability to observe another extreme in $Δt$ time since the last extreme happened $t$ time ago. Furthermore, an extreme predicting model based on RIA-EVT-Copula is proposed by applying a decision-making algorithm on the hazard probability. Both in-sample and out-of-sample tests reveal that this new extreme forecasting framework has better performance in prediction comparing with the forecasting model based on the hazard probability only estimated from the distribution of recurrence intervals. Our results not only shed a new light on understanding the occurring pattern of extremes in financial markets, but also improve the accuracy to predict financial extremes for risk management.