Random proportional Weibull hazard model for large-scale information systems
نویسندگان
چکیده
Purpose – This study aims to focus on asset management of large-scale information systems supporting infrastructures and especially seeks to address a methodology of their statistical deterioration prediction based on their historical inspection data. Information systems are composed of many devices. Deterioration process i.e. wear-out failure generation process of those devices is formulated by a Weibull hazard model. Furthermore, in order to consider the heterogeneity of the hazard rate of each device, the random proportional Weibull hazard model, which expresses the heterogeneity of the hazard rate as random variables, is to be proposed. Design/methodology/approach – Large-scale information systems comprise many components, and different types of components might have different hazard rates. Therefore, when analyzing faults of information systems that comprise various types of devices and components, it is important to consider the heterogeneity of the hazard rates that exist between the different types of components. In this study, with this in consideration, the random proportional Weibull hazard model, whose heterogeneity of hazard rates is subject to a gamma distribution, is formulated and a methodology is proposed which estimates the failure rate of various components comprising an information system. Findings – Through a case study using a traffic control system for expressways, the validity of the proposed model is empirically verified. Concretely, as for HDD, the service life at which the survival probability is 50 percent is estimated as 158 months. However, even for the same HDD, use environment differs according to usage. Actually, among the three different usages (PC, server, others), failures happen earliest in the case of PCs, which have the highest heterogeneity parameter and a survival probability of 50 percent after 135 months of usage. On the other hand, as for others, its survival probability is 50 percent at 303 months. Originality/value – To operationally express the heterogeneity of failure rates, the Weibull hazard model is employed as a base, and a random proportional Weibull hazard model expressing the proportional heterogeneity of hazard rates with a standard gamma distribution is formulated. By estimating the parameter of the standard proportional Weibull hazard function and the parameter of the probability distribution that expresses the heterogeneity of the proportionality constant between the types, the random proportional Weibull hazard model can easily express the heterogeneity of the hazard rates between types and components.
منابع مشابه
Random Proportional Weibull Hazard Model for Predicting Deterioration of Educational Facilities
In asset management of infrastructures, predicting deterioration of structures is one of an essential technique. Especially this study focuses on educational facilities from among social infrastructures. However, as for such kind of the facilities that consist of a large number of structural components, in order to estimate their deterioration process with high accuracy, the heterogeneity of in...
متن کاملUsing of frailty model baseline proportional hazard rate in Real Data Analysis
Many populations encountered in survival analysis are often not homogeneous. Individuals are flexible in their susceptibility to causes of death, response to treatment and influence of various risk factors. Ignoring this heterogeneity can result in misleading conclusions. To deal with these problems, the proportional hazard frailty model was introduced. In this paper, the frailty model is ex...
متن کاملSurvival analysis of thalassemia major patients using Cox, Gompertz proportional hazard and Weibull accelerated failure time models
Background: Thalassemia major (TM) is a severe disease and the most common anemia worldwide. The survival time of the disease and its risk factors are of importance for physicians. The present study was conducted to apply the semi-parametric Cox PH model and use parametric proportional hazards (PH) and accelerated failure time (AFT) models to identify the risk factors related to survival of TM ...
متن کاملHeritability, reliability of genetic evaluations and response to selection in proportional hazard models.
The purposes of this study were 1) to investigate the heritability, reliability, and selection response for survival traits following a Weibull frailty proportional hazard model; and 2) to examine the relationship between genetic parameters from a Weibull model, a discrete proportional hazard model, and a binary data analysis using a linear model. Both analytical methods and Monte Carlo simulat...
متن کاملAsset Management System for Educational Facilities Considering the Heterogeneity in Deterioration Process
In asset management of infrastructures, predicting deterioration of structures is one of an essential technique to make a decision on the optimal maintenance policy. However, as for large-scaled infrastructures that consist of a huge number of structural components, in order to estimate their deterioration process with high accuracy, the heterogeneity of individual components has to be consider...
متن کامل