Abstract This paper considers optimum plans for failure-step stress partially accelerated life tests with two stress levels under type-II censoring assuming Weibull distribution as a lifetime model. The optimum test plans determine the optimum proportion of test units failing at each stress according to a certain optimality criterion. The D-optimality criterion is considered. Some numerical ill...

We study the asymptotic distribution of the statistics suggested by Sargan/Byron/Wegge and Basmann for testing for over-identification in partially identified linear structural equations and derive closed form expressions for their asymptotic densities. These allow us to understand the asymptotic behaviour of these statistics in cases where identification of the structural parameters fails. We ...

Cragg and Donald (1996) have pointed out that the asymptotic size of tests for overidentifying restrictions can be much smaller than the asymptotic nominal size when the structural equation is partially identified. This may lead to misleading inference if the critical values are obtained from a chi-square distribution. To overcome this problem we derive the exact asymptotic distribution of the ...

Interest often focuses on estimating sensitivity and specificity of a group of raters or a set of new diagnostic tests in situations in which gold standard evaluation is expensive or invasive. Various authors have proposed semilatent class modeling approaches for estimating diagnostic accuracy in this situation. This article presents imputation approaches for this problem. I show how imputation...

This study considers Rao test and Wald test for adaptive detection based on a diversely polarized antenna (DPA) in partially homogeneous environment. The theoretical expressions for the probability of false alarm and detection are derived, and constant false alarm rate (CFAR) behaviour is remarked on. Furthermore, the monotonicities of detection probability of the two detectors are proved, and ...

In this paper, we have studied the estimation of parameters under failure censored data using step stress partially accelerated life testing. The lifetimes of test items are assumed to follow Mukherjee-Islam distribution. The estimation of different parameters and acceleration factor are obtained by Maximum Likelihood Method. Relative absolute bias (RAB), mean squared error (MSE), relative erro...

a common fixed point result for weakly increasing mappings satisfying generalized contractive type of zhang in ordered metric spaces are derived.

In life-testing investigations, accelerated life testing is crucial since it reduces both time and costs. this study, constant-stress partially tests using adaptive progressively Type I censored samples are taken into account. This accomplished under the assumption that lifespan of products normal use conditions follows inverse Weibull distribution. addition to maximum likelihood approach, prod...