Saved in:
Bibliographic Details
Main Authors: Ke, Tianjun, Medina, Marco Avella
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2605.04317
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917504684654592
author Ke, Tianjun
Medina, Marco Avella
author_facet Ke, Tianjun
Medina, Marco Avella
contents We introduce a novel approach to finite sample robustness that avoids the pessimism of traditional breakdown analyses. We define the threshold breakdown point, the smallest contamination fraction needed to induce a prescribed deviation, and the finite sample m-sensitivity, the worst-case deviation that an estimator can incur after m observations are contaminated. We derive these measures for commonly used M-estimators, their standard errors and related test statistics. This allows us to extend the decision breakdown point of Zhang (1996) to obtain general breakdown characterizations for hypothesis testing, and show how these notions correspond to finite sample counterparts of the power and level breakdown functions of He, Simpson and Portnoy (1990). We complement our work with an inferential framework for the threshold breakdown and m-sensitivity that yields consistency and asymptotic normality results, as well as a valid multiplier bootstrap for uncertainty quantification. We illustrate the practical utility of our methods in various numerical examples and an application to a two sample testing problem for a blood pressure dataset.
format Preprint
id arxiv_https___arxiv_org_abs_2605_04317
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The Threshold Breakdown Point
Ke, Tianjun
Medina, Marco Avella
Statistics Theory
We introduce a novel approach to finite sample robustness that avoids the pessimism of traditional breakdown analyses. We define the threshold breakdown point, the smallest contamination fraction needed to induce a prescribed deviation, and the finite sample m-sensitivity, the worst-case deviation that an estimator can incur after m observations are contaminated. We derive these measures for commonly used M-estimators, their standard errors and related test statistics. This allows us to extend the decision breakdown point of Zhang (1996) to obtain general breakdown characterizations for hypothesis testing, and show how these notions correspond to finite sample counterparts of the power and level breakdown functions of He, Simpson and Portnoy (1990). We complement our work with an inferential framework for the threshold breakdown and m-sensitivity that yields consistency and asymptotic normality results, as well as a valid multiplier bootstrap for uncertainty quantification. We illustrate the practical utility of our methods in various numerical examples and an application to a two sample testing problem for a blood pressure dataset.
title The Threshold Breakdown Point
topic Statistics Theory
url https://arxiv.org/abs/2605.04317