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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.
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273 questions
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How can I predict using an AFT model with the survival package in R?

I am using an accelerated failure time / AFT model with a weibull distribution to predict data. I am doing this using the survival package in R. I am splitting my data in training and test, do training on the training set and afterwards try to…
User12547645
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Combining two Weibull distributions in R

I am working on a project which involves combining two Weibull distributions and thus creating a double peaked curve. I then aim to make predictions using this. I have searched online and I can't seem to find anything on this or if R has a function…
Fiona
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The Weibull distribution in R (ExtDist)

Has anyone had problems with the Weibull distribution using the ExtDist Package? From the documentation: Parameter Estimation for a distribution with unknown shape parameters Example from: Rinne (2009) Dataset p.338 and example pp.418-419 …
James
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Maximum Likelihood Estimation for three-parameter Weibull distribution in r

I want to estimate the scale, shape and threshold parameters of a 3p Weibull distribution. What I've done so far is the following: Refering to this post, Fitting a 3 parameter Weibull distribution in R I've used the functions EPS =…
Tim-TU
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A simple model in Winbugs but it says "This chain contains uninitialized variables"

I have some simple time to event data, no covariates. I was trying to fit a Weibull distribution to it. So I have the following code. Everything looks good until I load my initials. It says "this chain contains uninitialized variables". But I don't…
user3669725
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R: Trying to create a Q-Q plot for the Weibull Distribution, getting error "NAs Introduced by Coersion"

I am trying to create a Q-Q plot to test if my data can be modeled by the Weibull distribution using the command qqplot(x,'weibull') using the data in x =c(3.367, 0.769,0.8,1,1.2) I keep getting presented with with the error "In xy.coords(x,…
Thomas Worm
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Fitting a curve to weibull distribution in R using nls

I am trying to fit this data to a weibull distribution: My x and y variables are: y <- c(1, 1, 1, 4, 7, 20, 7, 14, 19, 15, 18, 3, 4, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1) x <- c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,…
Aditya Bhatia
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Simulate competing risk data

My goal is to simulate a data set that can be used to test a competing risk model. I am just trying a simple example with the survsim::crisk.sim function but it does not lead to the results I expect. require(survival) simulated_data <-…
Stereo
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Events in R EHA

I prepared a data set to perform an event history analysis. When I do a count of the number of events, > event_info[, .(sum(event))] V1 1: 4102 When I run, library(eha) reliability <- aftreg(Surv(tstart, tstop, event) ~ 1, dist…
Stereo
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confidence interval for MTTF - Weibull survival curve in R

I am trying to implement the Delta Method in R to calculate the MTTF variance of a Weibull survival curve. The shape parameter is alpha and scale parameter is delta. Variance = var; covariance = cov. The equation is: var(mttf) =…
Vinicius_rr
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Something off with survreg in R?

While trying to fit a Weibull proportional hazard model togehan data in R, I noticed that changing the order of thegehan data changes the output. library(MASS) library(survival) attach(gehan) survreg(Surv(time, cens) ~ treat, gehan, dist =…
Günal
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How to determine weibull parameters for a left truncated distribution using fitdistr?

I hope to find weibull shape and scale parameters for a distribution that is left truncated using R's fitdistr function (MLE). Using a sample of data of tree diameters (the smallest of which being…
treetopdewdrop
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Scipy Weibull CDF calculation

I'm doing survival calculations in Scipy and can't get the correct values. My code: x, a, c = 1000, 1.5, 5000 vals = exponweib.cdf(x,a,c,loc=0,scale=1) vals should equal 0.085559356392783004, but I'm getting 0 instead. If I define my own function…
Brandon Booth
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Calculating standard deviations in Stata to approximate beta distributions

My question relates to calculating the standard deviation (SD) of transition probabilities derived from coefficients estimated through Weibull regression in Stata. The transition probabilities are being used to model disease progression of leukemia…
Emily
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How can I apply "sapply" in R with multiple codes in one function?

I am a new R user. I have a simple sapply function example for calculating mean and sd for a splitted data frame. My data contains half hourly wind speed with direction. I want to know daily Weibull distribution for my study for 13 years. That is…
Kangmin
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