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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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Representing Parametric Survival Model in 'Counting Process' form in JAGS

I'm trying to build a survival model in JAGS that allows for time-varying covariates. I'd like it to be a parametric model — for example, assuming survival follows the Weibull distribution (but I'd like to allow the hazard to vary, so exponential is…
jwdink
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Fitting a Weibull distribution using Scipy

I am trying to recreate maximum likelihood distribution fitting, I can already do this in Matlab and R, but now I want to use scipy. In particular, I would like to estimate the Weibull distribution parameters for my data set. I have tried…
kungphil
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How to plot the survival curve generated by survreg (package survival of R)?

I’m trying to fit and plot a Weibull model to a survival data. The data has just one covariate, cohort, which runs from 2006 to 2010. So, any ideas on what to add to the two lines of code that follows to plot the survival curve of the cohort of…
rm.
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Plot survival and hazard function of survreg using curve()

I have the following survreg model: Call: survreg(formula = Surv(time = (ev.time), event = ev) ~ age, data = my.data, dist = "weib") Value Std. Error z p (Intercept) 4.0961 0.5566 7.36 1.86e-13 age 0.0388 …
user1252482
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How to scale/transform graphics::plot() axes with any transformation, not just logarithmic (for Weibull plots)?

I am building an R package to display Weibull plots (using graphics::plot) in R. The plot has a log-transformed x-axis and a Weibull-transformed y-axis (for lack of a better description). The two-parameter Weibull distribution can thus be…
user2257135
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Interpreting Weibull parameters from survreg

I am trying to generate an inverse Weibull distribution using parameters estimated from survreg in R. By this I mean I would like to, for a given probability (which will be a random number in a small simulation model implemented in MS Excel), return…
DavidT85
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Modelling data with a Weibull link function in R

I am trying to model some data that follows a sigmoid curve relationship. In my field of work (psychophysics), a Weibull function is usually used to model such relationships, rather than probit. I am trying to create a model using R and am…
CaptainProg
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Fit distribution to given frequency values in R

I have frequency values changing with the time (x axis units), as presented on the picture below. After some normalization these values may be seen as data points of a density function for some distribution. Q: Assuming that these frequency points…
Marta Karas
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Fitting a 3 parameter Weibull distribution

I have been doing some data analysis in R and I am trying to figure out how to fit my data to a 3 parameter Weibull distribution. I found how to do it with a 2 parameter Weibull but have come up short in finding how to do it with a 3 parameter.…
Matthew Crews
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Fitting data to multimodal distributions with scipy, matplotlib

I have a dataset that I would like to fit to a known probability distribution. The intention is to use the fitted PDF in a data generator - such that I can sample data from the known (fitted) PDF. Data will be used for simulation purposes. At the…
Rosh
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How to random sample a 2-parameter weibull distribution in python

I was wondering how to generate a random weibull distribution with 2-parameter (lambda, k) in python. I know that numpy has a numpy.random.weibull, but it only accepts the a parameter as the shape of the distribution.
Víctor Navarro
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How to code a multiparameter log-likelihood function in R

I would like to estimate power of the following problem. I am interested in comparing two groups that both follow Weibull distribution. So, group A has two parameters (shape par = a1,scale par = b1) and two parameters has group B (a2, b2). By…
user36478
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Weibull Parameter estimation using Apache Commons Math

I need to estimate the shape and scale parameters of a Weibull distribution from a sample data using MLE. I checked the WeibullDistribution class of Apache commons Math but it doesn't have such functionality. Any suggestion? I need to use the class…
Tesse M
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Determine Weibull parameters from data

I would like to identify the Weibull parameters (i.e. the shape and scale) of my data. 0.022988506 0.114942529 0.218390805 0.114942529 0.149425287 0.114942529 0.068965517 0.068965517 0.034482759 0.022988506 0.022988506 0.022988506 0.022988506 I've…
larual
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How to do simple survival analysis with pymc3 (Weibull distribution regression)?

I'm new to using pymc3, I've read Bayesian Methods for Hackers and done my best to work through existing survival analysis tutorials in pymc3. However, I don't understand how to write/interpret the "survival function". For this problem, I've…
Noah
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