125 – Reliability
Optimal Step-Stress Tests for Exponential Failure Data Under Progressive Type-I Censoring
David Han
The University of Texas at San Antonio
Tony Ng
Southern Methodist University
A k-step-stress accelerated life-testing is considered with an equal step duration. For small to moderate sample sizes, a practical modification is suggested in order to guarantee a feasible k-step-stress test under progressive Type-I censoring, and the optimal step duration is determined under this model. Next, we discuss the determination of optimal step duration under the condition that the step-stress test proceeds to the k-th stress level, and the efficiency of this conditional inference is compared to that of the previous case. In all cases considered, censoring is allowed at each point of stress change. The determination of optimal step duration is discussed under C-optimality, D-optimality, and A-optimality criteria. We investigate the case of progressively Type-I right censored data from an exponential distribution with a single stress variable.
