Adaptive Matrix Change Point Detection: Leveraging Structured Mean Shifts

Fuente: arXiv
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Autori principali: Zhang, Xinyu, Chan, Kung-Sik
Natura: Preprint
Pubblicazione: 2024
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author Zhang, Xinyu
Chan, Kung-Sik
author_facet Zhang, Xinyu
Chan, Kung-Sik
contents In high-dimensional time series, the component processes are often assembled into a matrix to display their interrelationship. We focus on detecting mean shifts with unknown change point locations in these matrix time series. Series that are activated by a change may cluster along certain rows (columns), which forms mode-specific change point alignment. Leveraging mode-specific change point alignments may substantially enhance the power for change point detection. Yet, there may be no mode-specific alignments in the change point structure. We propose a powerful test to detect mode-specific change points, yet robust to non-mode-specific changes. We show the validity of using the multiplier bootstrap to compute the p-value of the proposed methods, and derive non-asymptotic bounds on the size and power of the tests. We also propose a parallel bootstrap, a computationally efficient approach for computing the p-value of the proposed adaptive test. In particular, we show the consistency of the proposed test, under mild regularity conditions. To obtain the theoretical results, we derive new, sharp bounds on Gaussian approximation and multiplier bootstrap approximation, which are of independent interest for high dimensional problems with diverging sparsity.
format Preprint
id arxiv_https___arxiv_org_abs_2401_17473
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Adaptive Matrix Change Point Detection: Leveraging Structured Mean Shifts
Zhang, Xinyu
Chan, Kung-Sik
Methodology
Statistics Theory
In high-dimensional time series, the component processes are often assembled into a matrix to display their interrelationship. We focus on detecting mean shifts with unknown change point locations in these matrix time series. Series that are activated by a change may cluster along certain rows (columns), which forms mode-specific change point alignment. Leveraging mode-specific change point alignments may substantially enhance the power for change point detection. Yet, there may be no mode-specific alignments in the change point structure. We propose a powerful test to detect mode-specific change points, yet robust to non-mode-specific changes. We show the validity of using the multiplier bootstrap to compute the p-value of the proposed methods, and derive non-asymptotic bounds on the size and power of the tests. We also propose a parallel bootstrap, a computationally efficient approach for computing the p-value of the proposed adaptive test. In particular, we show the consistency of the proposed test, under mild regularity conditions. To obtain the theoretical results, we derive new, sharp bounds on Gaussian approximation and multiplier bootstrap approximation, which are of independent interest for high dimensional problems with diverging sparsity.
title Adaptive Matrix Change Point Detection: Leveraging Structured Mean Shifts
topic Methodology
Statistics Theory
url https://arxiv.org/abs/2401.17473