An artificial neural network (ANN) model for predicting the failure rate of De Havilland Dash-8 airplane tires utilizing the twolayered feed-forward back-propagation algorithm as a learning rule is developed. The inputs to the neural network are independent variables and the output is the failure rate of the tires. Six years of data are used for model building and validation. Model validation, ...

We exhibit a new stability property of Weibull tail-distributions. It is shown that the power of a random variable with a Weibull tail-distribution still has a Weibull tail-distribution and the associated Weibull tail-coefficient is exhibited. Weibull tail-distributions are defined through their distribution function by:

This report explains Weibull plotting and its rationale. It shows how the two Weibull parameter estimates are easily read off from the Weibull plot. The use of Weibull plotting is introduced first in the context of complete samples and then extended to two common forms of censoring: type I or multiple censoring and type II censoring. Two blank Weibull plotting templates are provided, one for a ...

For β = 1 the Weibull distribution coincides with the exponential distribution with mean α. In general, α represents the .632-quantile of the Weibull distribution regardless of the value of β since Fα,β(α) = 1 − exp(−1) ≈ .632 for all β > 0. Figure 1 shows a representative collection of Weibull densities. Note that the spread of the Weibull distributions around α gets smaller as β increases. Th...

We study the properties of the called log-beta Weibull distribution defined by the logarithm of the beta Weibull random variable (Famoye et al., 2005; Lee et al., 2007). An advantage of the new distribution is that it includes as special sub-models classical distributions reported in the lifetime literature. We obtain formal expressions for the moments, moment generating function, quantile func...

We propose a new class of distributions called the Lomax generator with two extra positive parameters to generalize any continuous baseline distribution. Some special models such as the Lomax-normal, Lomax–Weibull, Lomax-log-logistic and Lomax–Pareto distributions are discussed. Some mathematical properties of the new generator including ordinary and incomplete moments, quantile and generating ...

Prior to modern typing methods, cross-infection of P. aeruginosa between people with cystic fibrosis (CF) was felt to be rare. Recently a number of studies have demonstrated the presence of clonal strains of P. aeruginosa infecting people with CF. The aim of this study was to determine whether strains of P. aeruginosa demonstrated differences in resistance to desiccation and whether preincubati...

This work aims to study the factors that increase risk of death hospitalized patients diagnosed with COVID-19 through odd log-logistic regression model for censored data two systematic components, as well provide new mathematical properties this distribution. To achieve this, a dataset individuals residing in city Campinas (Brazil) was used and simulations were performed investigate accuracy ma...

Choose the Cox proportional hazards regression model if the values in your dependent variable are duration observations. The advantage of the semi-parametric Cox proportional hazards model over fully parametric models such as the exponential or Weibull models is that it makes no assumptions about the shape of the baseline hazard. The model only requires the proportional hazards assumption that ...