Sponsor
Publication of this article in an open access journal was funded by the Portland State University Library’s Open Access Fund.
Published In
Probability in Engineering and Information Sciences
Document Type
Article
Publication Date
3-17-2022
Subjects
Probability and statistics
Abstract
Let X1,…,Xn be mutually independent exponential random variables with distinct hazard rates λ1,…,λn > 0 and let Y1,…,Yn be a random sample from the exponential distribution with hazard rate $\bar \lmd = \sum_{i=1}^n \lmd_i/n$. Also let X1:n < ⋯ < Xn:n and Y1:n < ⋯ < Yn:n be their associated order statistics. It is shown that for 1 ≤ i < j ≤ n, the generalized spacing Xj:n - X i:n is more dispersed than Yj:n− Yi:n according to dispersive ordering. This result is used to solve a long standing open problem that for 2 ≤ i ≤ n the dependence of Xi:n on X1:n is less than that of Yi:n on Y1:n, in the sense of the more stochastically increasing. This dependence result is also extended to the PHR model. This extends the earlier work of {\em Genest, Kochar and Xu}[ J.\ Multivariate Anal.\ {\bf 100} (2009) \ 1587-1592] who proved this result for i=n.
Rights
© The Author, 2022. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
DOI
10.1017/S0269964822000146
Persistent Identifier
https://archives.pdx.edu/ds/psu/37228
Citation Details
Kochar, Subhash C., (2022). [PRE-PRINT] "Dependence Comparisons of Order Statistics in the Proportional Hazards Model," To be published in Probability in Engineering and Information Sciences.