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Questions tagged [weibull]

The Weibull distribution is a probability distribution with applications in survival analysis, reliability engineering, failure analysis, industrial engineering, extreme value theory, weather forecasting, forestry, and more.

References

Wikipedia article

Tag usage

Questions on should be about implementation and programming problems, not about the statistical or theoretical properties of the technique.
Consider whether your question might be better suited to Cross Validated, the StackExchange site for statistics, machine learning and data analysis.

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error in coxph.wtest when using survreg and weibull in survival package, R

I am using survreg function and weibull distribution to predict the survival time for the last row of my data, But I got the error message. My data is: Train <- data.frame(Sum=c(2,2,2,2,2), Days=c(21,21,21,21,21), …
Feng Chen
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Set seed for Weibull distribution

In my C# code I need to create a Weibull random variable like this: Weibull myVar= new Weibull(3, 5); However, I would also like to set a seed so that the random numbers generated by this object are the same each time I run my program. In other…
BJPrim
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Wind Speed time series simulation in R

Following up from an R blog which is interesting and quite useful to simulate the time series of an unknown area using its Weibull parameters. Although this method gives a reasonably good estimate of time series as a whole it suffers a great deal…
SamAct
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How to alter one weibull curve to approximate another weibull curve?

I have one data set that I wish to calibrate to another. What makes this tricky is I do not have the full distribution, I have count data. I know that the distribution is supposed to be Weibull, so I created 2 Weibull curves, but I am then uncertain…
Danielle Watts
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Is possible to define a random limit for a loop in JAGS?

I am trying to implement a Weibull proportional hazards model with a cure fraction following the approach outlined by Hui, Ibrahim and Sinha (1999) - A New Bayesian Model for Survival Data with a Surviving Fraction. However, I am not sure if it is…
Márcio Augusto Diniz
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Bayesian confidence limits for cumulative distribution function

I applied Bayesian approach to a set of highly censored failure data using Metropolis-Hastings method and now I have a sample of parameter values from the marginal posterior distributions. The failure model used is the Weibull distribution. Can…
Nayomi
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Fit Weibull to distribution with genextreme and weibull_min

Using SciPy, I am trying to reproduce the weibull fit from this question. My fit looks good when I use the genextreme function as follows: import numpy as np from scipy.stats import genextreme import matplotlib.pyplot as…
Oliver Angelil
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Random weibull from mean and variance

I need to sample random values from a Weibull distribution where I know the mean and the variance. I want to use Matlab, whose function wblrnd requires the shape and scale parameters. Now, I have seen from wikipedia that mean and variance are…
Patapunfate
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Generating random numbers in a specific interval

I want to generate some Weibull random numbers in a given interval. For example 20 random numbers from the Weibull distribution with shape 2 and scale 30 in the interval (0, 10). rweibull function in R produce random numbers from a Weibull…
Nayomi
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Fitting weibull model with nls

I'm not an expert in R, and I'm trying to fit thermal-death bacteria data to a weibull…
Cesar Alejandro Perez Fernande
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Scaling for estimating scale and shape parameter with fitdist function (fitdistrplus package)

As specified in the title I have a scaling problem with the fitdist function in R (fitdistrplus package). Please have a look at the following code: # Initialize arrays for storing result fit_store_scale <- rep(NA, 3) fit_store_shape <- rep(NA, 3) #…
titus24
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R Survival Analysis: error in survreg using Weibull

I'm trying to replicate some survival analysis using the Weibull distribution that I have previously produced in SAS - I'm now working from an unlicensed machine so am using R (both from Windows). My (right censored) input data looks like: >…
Zephyr
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Programmatically create and visualize parametric survival curves without covariates in R

I'm trying to plot parametric survival curves for lognormal, exponential,log logistic and weibull distributions using AFT models. Following is the toy example: library(survival) library(ISwR) require(flexsurv) ln.curves <- flexsurvreg(Surv(days,…
forecaster
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Random number generation with weibull distribution in java

I want to generate random number from a weibull distribution with given shape and scale factor. I used the below code but the values generated are always close to beta. How to change the range of values? public double weibull(double eta, double…
Namit Agrawal
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Fiting Weibull using R2OpenBUGS

Because the estimation of the parameters of the Weibull function using R2OpenBUGS is so different from the amounts provided to generate the data set using rweibull? What's wrong with my fit? data<-rweibull(200, 2, 10) model<-function(){ v ~…
Ludian Vitorelo
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