论文标题
动态可解释的变更点检测
Dynamic Interpretable Change Point Detection
论文作者
论文摘要
在时间序列中确定变更点(CP)对于指导在金融和医疗保健等各个领域的更好决策以及促进对潜在风险或机会的及时回应。现有的变更点检测(CPD)方法在跟踪多维特征联合分布的变化方面有一个限制。此外,由于不同类型的CP可能需要不同的检测方法,它们无法在同一时间序列中有效地概括。随着多维时间序列的体积不断增长,捕获各种类型的复杂CP,例如时间序列特征的相关结构的变化变得至关重要。为了克服现有方法的局限性,我们提出了TivACPD,这种方法使用时间变化的图形套索(TVGL)来识别多维特征随时间时间之间的相关模式的变化,并将其与汇总内核最大值的均值差异(MMD)测试结合在一起,以确定在固定时间内的固定时间内的固定时间内的变化。 MMD和TVGL得分是使用一种基于相似性测量的新型集合方法组合的,该方法利用了这两种统计测试的能力。我们评估了TIVACPD在识别和表征各种CP的性能时的性能,并表明我们的方法在现实世界中CPD数据集中的当前最新方法优于当前的最新方法。我们进一步证明,TIVACPD的分数表征了CPS的类型并促进了变化动态的解释,从而提供了对现实生活应用的见解。
Identifying change points (CPs) in a time series is crucial to guide better decision making across various fields like finance and healthcare and facilitating timely responses to potential risks or opportunities. Existing Change Point Detection (CPD) methods have a limitation in tracking changes in the joint distribution of multidimensional features. In addition, they fail to generalize effectively within the same time series as different types of CPs may require different detection methods. As the volume of multidimensional time series continues to grow, capturing various types of complex CPs such as changes in the correlation structure of the time-series features has become essential. To overcome the limitations of existing methods, we propose TiVaCPD, an approach that uses a Time-Varying Graphical Lasso (TVGL) to identify changes in correlation patterns between multidimensional features over time, and combines that with an aggregate Kernel Maximum Mean Discrepancy (MMD) test to identify changes in the underlying statistical distributions of dynamic time windows with varying length. The MMD and TVGL scores are combined using a novel ensemble method based on similarity measures leveraging the power of both statistical tests. We evaluate the performance of TiVaCPD in identifying and characterizing various types of CPs and show that our method outperforms current state-of-the-art methods in real-world CPD datasets. We further demonstrate that TiVaCPD scores characterize the type of CPs and facilitate interpretation of change dynamics, offering insights into real-life applications.