Sampling plans in which items that are put to test, to collect the life of the items in order to decide upon accepting or rejecting a submitted lot, are called reliability test plans. The basic probability model of the life of the product is specified as the well-known log-logistic distribution...

Designed experiments are a key component in many companies' improvement strategies. Because completely randomized experiments are not always reasonable from a cost or physical perspective, split-plot experiments are prevalent. The recommended analysis accounts for the different sources of...

A new model combining parametric and semi-parametric approaches and following the lines of a semi-Markov model is developed for multi-stage processes. A Bivariate sojourn time distribution derived from the bivariate exponential distribution of Marshall & Olkin (1967) is adopted. The results...

Technical efficiency, which is a measure of production performance of a firm, has been estimated generally using a primal production frontier. Since the estimation is carried out for a given level of inputs, the efficiency measure includes the effect of 'input-mix' or 'input-allocation' and...

The purpose of this paper is to discuss the interpretation of dispersion effects in un-replicated fractional factorials from a robust design perspective. We propose an interpretation of dispersion effects as manifested interactions between control factors and unobserved and uncontrolled factors,...

The Cochran-Armitage test is the most frequently used test for trend among binomial proportions. This test can be performed based on the asymptotic normality of its test statistic or based on an exact null distribution. As an alternative, a recently introduced modification of the...

Experimental design and Taguchi's parameter design are widely employed by industry to optimize the process/product. However, censored data are often observed in product lifetime testing during the experiments. After implementing a repetitious experiment with type II censored data, the censored...

The tightened-normal-tightened (TNT) attributes sampling scheme was devised by Calvin (1977). In this paper, a TNT Scheme with variables sampling plan as the reference plan, designated as TNTVSS (nσ; kT, kN) is introduced, where nσ is the sample size under the reference plan, and kT and kN are...

This article is aimed at the investigation of some properties of the Weibull cumulative exposure model on multiple-step step-stress accelerated life test data. Although the model includes a probabilistic idea of Miner's rule in order to express the effect of cumulative damage in fatigue, our...

To estimate the total number of distinct species in a given region, Bayesian methods along with quadrat sampling procedures have been used by several authors. A key underlying assumption relies on the independence among the species. In this note, we analyse these estimates allowing a generalized...