The Gaussian central limit theorem for a stationary time series with infinite variance

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Matsui, Muneya, Mikosch, Thomas
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908276638089216
author Matsui, Muneya
Mikosch, Thomas
author_facet Matsui, Muneya
Mikosch, Thomas
contents We consider a borderline case: the central limit theorem for a strictly stationary time series with infinite variance but a Gaussian limit. In the iid case a well-known sufficient condition for this central limit theorem is regular variation of the marginal distribution with tail index $α=2$. In the dependent case we assume the stronger condition of sequential regular variation of the time series with tail index $α=2$. We assume that a sample of size $n$ from this time series can be split into $k_n$ blocks of size $r_n\to\infty$ such that $r_n/n\to 0$ as $n\to\infty$ and that the block sums are asymptotically independent. Then we apply classical central limit theory for row-wise iid triangular arrays. The necessary and sufficient conditions for such independent block sums will be verified by using large deviation results for the time series. We derive the central limit theorem for $m$-dependent sequences, linear processes, stochastic volatility processes and solutions to affine stochastic recurrence equations whose marginal distributions have infinite variance and are regularly varying with tail index $α=2$.
format Preprint
id arxiv_https___arxiv_org_abs_2503_15894
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The Gaussian central limit theorem for a stationary time series with infinite variance
Matsui, Muneya
Mikosch, Thomas
Probability
Statistics Theory
Primary 60F05, Secondary 60E10 60G70 62E20
We consider a borderline case: the central limit theorem for a strictly stationary time series with infinite variance but a Gaussian limit. In the iid case a well-known sufficient condition for this central limit theorem is regular variation of the marginal distribution with tail index $α=2$. In the dependent case we assume the stronger condition of sequential regular variation of the time series with tail index $α=2$. We assume that a sample of size $n$ from this time series can be split into $k_n$ blocks of size $r_n\to\infty$ such that $r_n/n\to 0$ as $n\to\infty$ and that the block sums are asymptotically independent. Then we apply classical central limit theory for row-wise iid triangular arrays. The necessary and sufficient conditions for such independent block sums will be verified by using large deviation results for the time series. We derive the central limit theorem for $m$-dependent sequences, linear processes, stochastic volatility processes and solutions to affine stochastic recurrence equations whose marginal distributions have infinite variance and are regularly varying with tail index $α=2$.
title The Gaussian central limit theorem for a stationary time series with infinite variance
topic Probability
Statistics Theory
Primary 60F05, Secondary 60E10 60G70 62E20
url https://arxiv.org/abs/2503.15894