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arXiv · 2011.06908

Weak convergence of the scaled jump chain and number of mutations of the Kingman coalescent

Abstract

The Kingman coalescent is a fundamental process in population genetics modelling the ancestry of a sample of individuals backwards in time. In this paper, in a large-sample-size regime, we study asymptotic properties of the coalescent under neutrality and a general finite-alleles mutation scheme, i.e. including both parent independent and parent dependent mutation. In particular, we consider a sequence of Markov chains that is related to the coalescent and consists of block-counting and mutation-counting components. We show that these components, suitably scaled, converge weakly to deterministic components and Poisson processes with varying intensities, respectively. Along the way, we develop a novel approach, based on a change of measure, to generalise the convergence result from the parent independent to the parent dependent mutation setting, in which several crucial quantities are not known explicitly.

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BibTeXRIS

Martina Favero, Henrik Hult. 2025-03-13. Weak convergence of the scaled jump chain and number of mutations of the Kingman coalescent. https://doi.org/10.1214/24-ejp1128

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