arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1909.08101math.STstat.MEstat.TH
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高维时间序列模型可检测区域边界附近跳跃大小变化点的推断

Inference on the change point with the jump size near the boundary of the region of detectability in high dimensional time series models

Abhishek Kaul, Venkata K Jandhyala, Stergios B Fotopoulos

摘要:

本文提出了一种具有潜在变点的高维时间序列模型中变点参数的投影最小二乘估计。重要的是,我们在跳跃大小可能接近可检测区域边界的设置下工作。所提出的方法产生一个最佳的收敛速率,尽管假设的模型和潜在的减少跳跃大小的高维。这个估计的极限分布推导出来,从而允许建设一个置信区间的位置的变化点。提出了实现最优投影最小二乘估计所需的次优估计。预步估计过程的目的也不可知地检测的情况下,没有变化点存在,从而消除了需要预先测试的存在的变化点的推理方法的实施。我们的结果是在一个一般的正定空间依赖设置,假设没有特殊的结构,这种依赖。所提出的方法被设计为高度可扩展的,并适用于非常大的数据。理论结果检测和估计的一致性和限制分布的数值支持通过蒙特卡洛模拟。

英文摘要:

We develop a projected least squares estimator for the change point parameter in a high dimensional time series model with a potential change point. Importantly we work under the setup where the jump size may be near the boundary of the region of detectability. The proposed methodology yields an optimal rate of convergence despite high dimensionality of the assumed model and a potentially diminishing jump size. The limiting distribution of this estimate is derived, thereby allowing construction of a confidence interval for the location of the change point. A secondary near optimal estimate is proposed which is required for the implementation of the optimal projected least squares estimate. The prestep estimation procedure is designed to also agnostically detect the case where no change point exists, thereby removing the need to pretest for the existence of a change point for the implementation of the inference methodology. Our results are presented under a general positive definite spatial dependence setup, assuming no special structure on this dependence. The proposed methodology is designed to be highly scalable, and applicable to very large data. Theoretical results regarding detection and estimation consistency and the limiting distribution are numerically supported via monte carlo simulations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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