English

Hidden regular variation for stochastic recursions with diagonal matrices

Probability 2025-10-28 v1

Abstract

We consider random vectors XX that satisfy the equation in law X=AX+BX=AX+B, where AA is a given random diagonal matrix and BB a given random vector, both independent of XX. It is well known by the works of Kesten and Goldie that the marginals of XX may exhibit heavy tails, with possibly different tail indices. In recent works (Damek 2025, Mentemeier and Wintenberger 2022) it was observed that asymptotic independence may occur despite strong dependencies in the entries of AA: The probability that both marginals are simultaneously large decays faster than the marginal probability of an extreme event; the tail measure is concentrated on the axis. In this work, we analyse the hidden regular variation properties of XX, that is, we find the proper scaling for which one observes simultaneous extremes.

Keywords

Cite

@article{arxiv.2510.23130,
  title  = {Hidden regular variation for stochastic recursions with diagonal matrices},
  author = {Ewa Damek and Sebastian Mentemeier},
  journal= {arXiv preprint arXiv:2510.23130},
  year   = {2025}
}
R2 v1 2026-07-01T07:07:22.521Z