Friedman vs Pólya

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Alves, Raphael, Rosales, Rafael A.
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866917181506191360
author Alves, Raphael
Rosales, Rafael A.
author_facet Alves, Raphael
Rosales, Rafael A.
contents Suppose an urn contains initially any number of balls of two colours. One ball is drawn randomly and then put back with $α$ balls of the same colour and $β$ balls of the opposite colour. Both cases, $β=0$ and $β>0$ are well known and correspond respectively to Pólya's and Friedman's replacement schemes. We consider a mixture of both of these: with probability $p\in(0,1]$ balls are replaced according to Friedman's recipe and with probability $1-p$ according to the one by Pólya. Independently of the initial urn composition and independently of $α$, $β$, and the value of $p>0$, we show that the proportion of balls of one colour converges almost surely to $\frac12$. The latter is the limit behaviour obtained by using Friedman's scheme alone, i.e. when $p=1$. Our result follows by adapting an argument due to D. S. Ornstein.
format Preprint
id arxiv_https___arxiv_org_abs_2502_16768
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Friedman vs Pólya
Alves, Raphael
Rosales, Rafael A.
Probability
Primary: 60F15, Secondary: 60G42, 60J05
Suppose an urn contains initially any number of balls of two colours. One ball is drawn randomly and then put back with $α$ balls of the same colour and $β$ balls of the opposite colour. Both cases, $β=0$ and $β>0$ are well known and correspond respectively to Pólya's and Friedman's replacement schemes. We consider a mixture of both of these: with probability $p\in(0,1]$ balls are replaced according to Friedman's recipe and with probability $1-p$ according to the one by Pólya. Independently of the initial urn composition and independently of $α$, $β$, and the value of $p>0$, we show that the proportion of balls of one colour converges almost surely to $\frac12$. The latter is the limit behaviour obtained by using Friedman's scheme alone, i.e. when $p=1$. Our result follows by adapting an argument due to D. S. Ornstein.
title Friedman vs Pólya
topic Probability
Primary: 60F15, Secondary: 60G42, 60J05
url https://arxiv.org/abs/2502.16768