TITLE:
On the Distribution of the Minimum or Maximum of a Random Number of i.i.d. Lifetime Random Variables
AUTHORS:
Francisco Louzada, Estela M. P. Bereta, Maria A. P. Franco
KEYWORDS:
Compounding Distributions; Distribution of the Maximum; Distribution of the Minimum; Probability Generating Function
JOURNAL NAME:
Applied Mathematics,
Vol.3 No.4,
April
27,
2012
ABSTRACT: Statisticians are usually concerned with the proposition of new distributions. In this paper we point out that a unified and concise derivation procedure of the distribution of the minimum or maximum of a random number N of indepen-dent and identically distributed continuous random variables Yi,{i = 1,2,…,N} is obtained if one compounds the probability generating function of N with the survival or the distribution func-tion of Yi. Expressions are then derived in closed form for the density, hazard and quantile func-tions of the minimum or maximum. The methodology is illustrated with examples of the distributions proposed by Adamidis and Loukas (1998), Kus (2007), Tahmasbi and Rezaei (2008), Barreto-Souza and Cribari-Neto (2009), Cancho, Louzada, and Barriga (2011) and Louzada, Roman and Cancho (2011).