An important problem in extreme-value theory is the estimation of the probability that a high-dimensional random vector falls into a given extreme failure set. This paper provides a parametric approach to this problem, based on a generalization of the tail pairwise dependence matrix (TPDM). The TPDM gives a partial summary of tail dependence for all pairs of components of the random vector. We propose an algorithm to obtain an approximate completely positive decomposition of the TPDM. The decomposition is easy to compute and applicable to moderate to high dimensions. Based on the decomposition, we obtain parameters estimates of a max-linear model whose TPDM is equal to that of the original random vector. We apply the proposed decomposition algorithm to industry portfolio returns and maximal wind speeds to illustrate its applicability.
翻译:极端价值理论中的一个重要问题是估计高维随机矢量落入特定极端故障集的概率。本文件根据对尾端双向依赖矩阵(TPDM)的概括性,提供了对这一问题的参数性方法。TPDM对随机矢量的所有组成部分的尾部依赖性进行了部分总结。我们提出了一个算法,以获得TPDM的大致完全正分解。分解很容易计算,并适用于中度至高度。根据分解,我们获得了一个最大线性模型的参数估计值,TPDM相当于原始随机矢量的参数。我们将拟议的分解算法应用于工业组合回报和最大风速,以说明其适用性。