## Electronic Communications in Probability

### Second order behavior of the block counting process of beta coalescents

#### Abstract

The Beta coalescents are stochastic processes modeling the genealogy of a population. They appear as the rescaled limits of the genealogical trees of numerous stochastic population models. In this article, we take interest in the number of blocs at small times in the Beta coalescent. Berestycki, Berestycki and Schweinsberg [2] proved a law of large numbers for this quantity. Recently, Limic and Talarczyk [9] proved that a functional central limit theorem holds as well. We give here a simple proof for an unidimensional version of this result, using a coupling between Beta coalescents and continuous-time branching processes.

#### Article information

Source
Electron. Commun. Probab., Volume 22 (2017), paper no. 61, 8 pp.

Dates
Accepted: 11 October 2017
First available in Project Euclid: 15 November 2017

https://projecteuclid.org/euclid.ecp/1510736418

Digital Object Identifier
doi:10.1214/17-ECP93

Mathematical Reviews number (MathSciNet)
MR3724559

Zentralblatt MATH identifier
1378.60109

#### Citation

Lin, Yier; Mallein, Bastien. Second order behavior of the block counting process of beta coalescents. Electron. Commun. Probab. 22 (2017), paper no. 61, 8 pp. doi:10.1214/17-ECP93. https://projecteuclid.org/euclid.ecp/1510736418

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