purpose: to evaluate the effect of age, sex, type of surgery, extent of retinal detachment (rd), vitreous incarceration in wound, and myopic degeneration on the rate of retinal redetachment following rd surgery using eternal weibull regression analysis. methods: we performed a survival analysis on a multi-center randomized controlled trial conducted on patients with pseudophakic or aphakic rd t...

We propose a new family of distributions referred to as Weibull taildistributions. This family is designed to model left tails with exponential behavior. The exponent can be estimated using inference procedures adapted from the Weibull tail-distributions literature. Let us define a negative Weibull tail-distribution through its distribution function by: F (x) = exp {

BACKGROUND The use of three-dimensional (3D) surface imaging is becoming more popular and accepted in the fields of Medicine and Dentistry. The present study aims to develop a technique to automatically localise and quantify soft-tissue asymmetry in adults using 3D facial scans. This may be applied as a diagnostic tool to monitor growth and dynamic changes and to evaluate treatment outcomes. ...

Recently, several attempts have been made to define new models that extend well-known distributions and at the same time provide great flexibility in modelling real data. We propose a new four-parameter model named the Weibull-power function (WPF) distribution which exhibits bathtub-shaped hazard rate. Some of its statistical properties are obtained including ordinary and incomplete moments, qu...

Abstract Statistical inferences of the parameters included in a competing risks model are presented. It is assumed here that the causes of failures may occur at times that follow modified Weibull distributions. The case of Weibull distributions can be derived as special case of the problem studied in this paper. The maximum likelihood procedure is used to get the point estimations and asymptoti...

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...

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 ...

The Weibull distribution is a very applicable model for the lifetime data. For inference about two Weibull distributions using records, the shape parameters of the distributions are usually considered equal. However, there is not an appropriate method for comparing the shape parameters in the literature. Therefore, comparing the shape parameters of two Weibull distributions is very important. I...