A summary of block replacement policies
A summary of replacement models with changing failure distributions
A tutorial on nonlinear time-series data mining in engineering asset health and reliability prediction: concepts, models, and algorithms.
Accelerated life models when the stress is not constant
Adaptive estimation of the conditional intensity of marker-dependent counting processes
We propose in this work an original estimator of the conditional intensity of a marker-dependent counting process, that is, a counting process with covariates. We use model selection methods and provide a nonasymptotic bound for the risk of our estimator on a compact set. We show that our estimator reaches automatically a convergence rate over a functional class with a given (unknown) anisotropic regularity. Then, we prove a lower bound which establishes that this rate is optimal. Lastly, we provide...
Additive hazards regression with case-cohort sampled current status data
In a case-cohort design, covariate histories are measured only on cases and a subcohort that is randomly selected from the entire cohort. This design has been widely used in large epidemiologic studies, especially when the exposures of interest are expensive to assemble for all the subjects. In this paper, we propose statistical procedures for analyzing case-cohort sampled current status data under the additive hazards model. Asymptotical properties of the proposed estimator are described and we...
Addressing the problem of lack of representativeness on syndromic surveillance schemes
A major concern with some contagious diseases has recently led to an enormous effort to monitor population health status by several different means. This work presents a modeling approach to overcome this poor data characteristic, allowing its use for the estimation of the true population disease picture. We use a state space model, where we run two processes in parallel - a process describing the non observable states of the population concerning the presence/absence of disease,...
Alternative parametric estimation in the exponential case under random censorship
An application of nonprarametric Cox regression model in reliability analysis: a case study
The contribution deals with an application of the nonparametric version of Cox regression model to the analysis and modeling of the failure rate of technical devices. The objective is to recall the method of statistical analysis of such a model, to adapt it to the real–case study, and in such a way to demonstrate the flexibility of the Cox model. The goodness-of-fit of the model is tested, too, with the aid of the graphical test procedure based on generalized residuals.
An Invariance Principle for Progressively Truncated Likelihood Ratio Statistics.
Análisis bayesiano de supervivencia basado en el modelo de Rayleigh: addendum.
In the printed version of the paper Bayesian survival analysis based on the Rayleigh model (Trabajos de Estadística Vol. 5, no. 1, 1990), figures num. 1, 2 and 3 mentioned on page 91 were not printed with the paper. That may create confusion and problems for the readers in understanding the conclusions, as in the absence of figures the paper is incomplete. For this reason we publish the figures in this issue.
Análisis de duración mediante un modelo lineal generalizado semiparamétrico.
Aitkin y Clayton (1980) proponen el análisis de modelos de duración mediante modelos lineales generalizados. En este trabajo extendemos esta metodología permitiendo que el efecto de alguna de las variables explicativas pueda no ser especificado. Así, el modelo propuesto es un modelo lineal generalizado semiparamétrico, con una componente paramétrica donde se especifica la forma funcional concreta del efecto de las variables explicativas sobre la duración, y una componente no paramétrica donde recogemos...
Analysis of a two-unit standby redundant system with three states of units
A cold-standby redundant system with two identical units and one repair facility is considered. Units can be in three states> good (I), degraded (II), and failed (III). We suppose that only the following state-transitions of a unit are possible: . The repair of a unit of the type can be interpreted as a preventive maintenance. Its realization depends on the states of both units. Several characteristics of the system (probabilities, distribution functions or their Laplace-Stieltjes transforms...
Analytical bootstrap methods for censored data.
Aplicación del método de regresión de Gehan y Siddiqui y el test de la F de Cox en el análisis de datos de supervivencia.
Este trabajo muestra algunas de las posibilidades de la estadística paramétrica en el análisis de datos de supervivencia en el campo de la toxicología y genética de poblaciones.La aplicación del método de regresión de Gehan y Siddiqui ha proporcionado un buen ajuste de los datos de supervivencia a una de las 4 distribuciones que contempla este método (Exponencial, Weibull, Gompertz y Exponencial lineal) en el 81% de los casos y de éstos en el 74% se han ajustado a una distribución Exponencial, mientras...
Apollo 13 Risk Assessment Revisited
Fault tree methodology is the most widespread risk assessment tool by which one is able to predict - in principle - the outcome of an event whenever it is reduced to simpler ones by the logic operations conjunction and disjunction according to the basics of Boolean algebra. The object of this work is to present an algorithm by which, using the corresponding computer code, one is able to predict - in practice - the outcome of an event whenever its fault tree is given in the usual form.
Application des lois non paramétriques dans les systèmes d’attente et la théorie de renouvellement
Les distributions non paramétriques de survie trouvent, de plus en plus, des applications dans des domaines très variés, à savoir : théorie de fiabilité et analyse de survie, files d’attente, maintenance, gestion de stock, théorie de l’économie, L’objet de ce travail est d’utiliser les bornes inférieures et supérieures (en terme de la moyenne) des fonctions de fiabilité appartenant aux classes de distribution de type et , présentées par Sengupta (1994), pour l’évaluation de certaines caractéristiques....
Application des lois non paramétriques dans les systèmes d'attente et la théorie de renouvellement
Les distributions non paramétriques de survie trouvent, de plus en plus, des applications dans des domaines très variés, à savoir: théorie de fiabilité et analyse de survie, files d'attente, maintenance, gestion de stock, théorie de l'économie, ... L'objet de ce travail est d'utiliser les bornes inférieures et supérieures (en terme de la moyenne) des fonctions de fiabilité appartenant aux classes de distribution de type IFR, DFR, NBU et NWU, présentées par Sengupta (1994), pour l'évaluation de...
Approche non paramétrique en théorie de la fiabilité : revue bibliographique
Approximation of reliability for a large system with non-markovian repair-times