A Martingale Approach to Large-$θ$ Ewens-Pitman Model

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Ribeiro, Rodrigo
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915213245153280
author Ribeiro, Rodrigo
author_facet Ribeiro, Rodrigo
contents We investigate the asymptotic behavior of the number of parts $K_n$ in the Ewens--Pitman partition model under the regime where the diversity parameter is scaled linearly with the sample size, that is, $θ= λn$ for some~$λ> 0$. While recent work has established a law of large numbers (LLN) and a central limit theorem (CLT) for $K_n$ in this regime, we revisit these results through a martingale-based approach. Our method yields significantly shorter proofs, and leads to sharper convergence rates in the CLT, including improved Berry--Esseen bounds in the case $α= 0$, and a new result for the regime $α\in (0,1)$, filling a gap in the literature.
format Preprint
id arxiv_https___arxiv_org_abs_2503_19892
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Martingale Approach to Large-$θ$ Ewens-Pitman Model
Ribeiro, Rodrigo
Probability
Statistics Theory
We investigate the asymptotic behavior of the number of parts $K_n$ in the Ewens--Pitman partition model under the regime where the diversity parameter is scaled linearly with the sample size, that is, $θ= λn$ for some~$λ> 0$. While recent work has established a law of large numbers (LLN) and a central limit theorem (CLT) for $K_n$ in this regime, we revisit these results through a martingale-based approach. Our method yields significantly shorter proofs, and leads to sharper convergence rates in the CLT, including improved Berry--Esseen bounds in the case $α= 0$, and a new result for the regime $α\in (0,1)$, filling a gap in the literature.
title A Martingale Approach to Large-$θ$ Ewens-Pitman Model
topic Probability
Statistics Theory
url https://arxiv.org/abs/2503.19892