School of Statistics, Capital University of Economics and Business, Beijing, China.
PLoS One. 2018 Nov 12;13(11):e0206753. doi: 10.1371/journal.pone.0206753. eCollection 2018.
The clustering of time series has attracted growing research interest in recent years. The most popular clustering methods assume that the time series are only linearly dependent but this assumption usually fails in practice. To overcome this limitation, in this paper, we study clustering methods applicable to time series with a general and dependent structure. We propose a copula-based distance to measure dissimilarity among time series and consider an estimator for it, where the strong consistency of the estimator is guaranteed. Once the pairwise distance matrix for time series has been obtained, we apply a hierarchical clustering algorithm to cluster the time series and ensure its consistency. Numerical studies, including a large number of simulations and analysis of practical data, show that our method performs well.
近年来,时间序列聚类引起了越来越多的研究兴趣。最流行的聚类方法假设时间序列仅具有线性相关性,但在实际中,这种假设通常不成立。为了克服这一限制,本文研究了适用于具有一般和相关结构的时间序列的聚类方法。我们提出了一种基于 Copula 的距离来衡量时间序列之间的差异,并考虑了它的一个估计量,保证了该估计量的强一致性。一旦获得了时间序列的两两距离矩阵,我们就可以应用层次聚类算法对时间序列进行聚类,并确保其一致性。包括大量模拟和实际数据分析在内的数值研究表明,我们的方法表现良好。