Table of Contents
ISRN Applied Mathematics
Volume 2011, Article ID 203618, 15 pages
Research Article

Estimating and Planning Accelerated Life Test Using Constant Stress for Generalized Logistic Distribution under Type-I Censoring

1Department of Mathematical Statistics, Institute of Statistical Studies and Research, Cairo University, Cairo 12613, Egypt
2Department of Statistics, Faculty of Economics and Political Science, Cairo University, Cairo, Egypt

Received 24 September 2011; Accepted 16 October 2011

Academic Editors: F. Jauberteau, T. Y. Kam, and S. Sture

Copyright © 2011 A. F. Attia et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The optimal designs and statistical inference of accelerated life tests under type-I are studied for constant stress-accelerated life tests (CSALTs). It is assumed that the lifetime at design stress has generalized logistic distribution. The scale parameter of the lifetime distribution at constant stress levels is assumed to be an inverse power law function of the stress level. The maximum likelihood (ML) estimators of the model parameters, Fisher information matrix, the asymptomatic variance-covariance matrix, the confidence bounds, the predictive value of the scale parameter, and the reliability function under the usual conditions are obtained under type-I censoring. Moreover, the optimal design of the accelerated life tests is studied according to the D-optimality criterion to specify the optimal censoring time. Finally, the numerical studies are introduced to illustrate the proposed procedures.