Abstract In this paper, we propose a new bivariateWeibull distribution and derive estimation and test procedures based on censored samples with common covariates. The study of bivariate Weibull was motivated by interesting biometrical applications. The maximum likelihood estimators for the model...

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 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 We propose frailty regression models in mixture distributions assuming the distribution of frailty to be a gamma distribution. We consider Weibull mixture as an example. There are some interesting situations like survival times in genetic epidemiology, dental implants of patients and...

Abstract In this paper a cold standby system consisting of two identical components (first component in working state and second one in the cold standby state) and one repairman is studied. A replacement policy is considered which is based on the number of down times in a renewal cycle. The...

In this paper, we compare the power of three different tests for testing zero and non-zero values of the parameter [lambda]3 which measures the degree of dependence between the two components in bivariate exponential distribution (BVED) of the Marshall-Olkin (1967) model. We also compare the...

The unknown or unobservable risk factors in the survival analysis cause heterogeneity between the individuals. Frailty models are used in the survival analysis to account for the unobserved heterogeneity in the individual risks to disease and death. In this paper, we suggest the shared gamma...

In this paper, we obtain MLEs of the parameters and of large sample test for testing independence and symmetry of k components in the k + 1 parameter version of an absolutely continuous multivariate exponential distribution (ACMVED) of Block (1975).

We propose a bivariate Weibull regression model with heterogeneity (frailty or random effect) which is generated by log-normal distribution. We assume that the bivariate survival data follow bivariate Weibull of [Hanagal, D.D., 2004. Parametric bivariate regression analysis based on censored...