Abstract The purpose of this paper is to derive an approximation of the reliability of a system with doubly bounded performance functions. The problem is illustrated through the probability of an n dimensional hyper cube of the multivariate normal distribution. An approximation method is...

Abstract A maximum likelihood estimation procedure is developed for a bivariate frailty regression model, in which dependence is generated by a gamma distribution. It is assumed that the random lifetimes follow a bivariate Weibull distribution proposed in Hanagal [Economic Quality Control 11:...

Abstract A generalization of the log-logistic distribution called exponentiated log-logistic distribution (in lines of exponentiated Weibull distribution suggested by Mudholkar and Srivastava [Technometrics 37: 436-445, 1995]) is considered. In this paper the operating characteristic for a...

Abstract Stochastic modelling has become a scientific catchword in many branches of science and in particular in quality theory. However, there are many misunderstandings concerning the term, and in many cases it is used wrongly. Therefore, this paper aims at introducing stochastic models, their...

Abstract A new control chart namely S pw -Chart for monitoring the changes in the process variability is proposed and is based on Probability Weighted Moments (PWMs) and assuming that the quality characteristic follows a normal distribution. The coefficients r 2 and r 3 (similar as the d 2 and d...

Abstract This paper extends the decomposition of marginal effects suggested by McDonald and Moffitt [The Review of Economics and Statistics 62: 318-321, 1980] to a nonlinear tobit model, considering the increasing use of tobit analysis and substantive economic implications of the decomposition....

Abstract A finite capacity Markovian queueing system with a number of heterogeneous channels depending on the system size is considered. The system consists of one regular channel and a maximum of c additional channels. When all the channels are in operation, the arrival rate is controlled...

Abstract In the area of stress-strength models there has been a large amount of work as regards estimation of the reliability R = Pr( X Y ). The algebraic form for R = Pr( X Y ) has been worked out for the vast majority of the well-known distributions when X and Y are independent random...

Abstract In this paper, we propose a new bivariate Weibull regression model based on censored samples with common covariates. There are some interesting biometrical situations which motivate the study of a bivariate Weibull regression model of the proposed type. A procedure for obtaining the...

Abstract A procedure is derived for determining the values of the parameters of a multinomial distribution by means of the fiducial approach proposed by Fisher. By decomposing the involved probability (mass or density) functions, it is shown that the resulting fiducial distributions belong to...