Journal of Statistical Theory and Practice

, Volume 6, Issue 4, pp 783–792

# Combined Tests for the Homogeneity of Weibull (or Extreme Value) Populations With Censored Data

• K. Thiagarajah
Article

## Abstract

A method of combining two independent test statistics to test the homogeneity of several Weibull (or extreme value) populations under censoring is considered. The procedures developed in this paper are based on Fisher’s method of combining two likelihood ratio statistics and two score statistics. The performance of these procedures are examined, through simulations, in terms of empirical size and power of the test statistics. We also develop two other statistics to test the equality of several Weibull scale parameters and shape parameters (or extreme value location and scale parameters) simultaneously. Simulation results show that the Fisher’s method of combining two independent statistics performs reasonably well under censoring.

## Keywords

Likelihood ratio statistic Score statistic Fisher’s method Extreme value distribution Censored data

## AMS 2000 Subject Classification

62N05 62N01 62F03

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