Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [winbugs]

Questions about BUGS language for defining Bayesian models that can be run by the WinBUGS software package. It is advised to supplement your question with a reproducible BUGS example (http://stackoverflow.com/q/5963269).

WinBUGS

WinBUGS is a software program for Bayesian analysis of complex statistical models using Markov chain Monte Carlo (MCMC) methods. WinBUGS implements the BUGS language for defining Bayesian models. WinBUGS was created by Dave Lunn, Andrew Thomas, Nicky Best, and David Spiegelhalter in 1996. In 2007 the last stable version (1.4.3) was released. Thereafter development focused on the OpenBUGS project.

Official WinBUGS Documentation

Other Documentation

89 questions
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Bayesian estimation of $N$ of a binomial distribution

This question is a technical follow-up of this question. I have trouble understanding and replicating the model presented in Raftery (1988): Inference for the binomial $N$ parameter: a hierarchical Bayes approach in WinBUGS/OpenBUGS/JAGS. It is not…
COOLSerdash
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Which is the best method for network meta-analysis?

There are now several different approaches to perform a network meta-analysis or mixed treatment comparison. The most commonly used and accessible ones are probably the following: in a Bayesian framework: design-by-treatment interaction approach…
Giuseppe Biondi-Zoccai
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Winbugs and other MCMC without information for prior distribution

What happens when you don't have an idea of the parameters distribution? What approach should we use? Most of the time we aim to undersatnd if a certain variable has any influence over the presence/absence of a certain species, and the variable is…
Gago-Silva
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How to get prediction for a specific variable in WinBUGS?

I am a new user of WinBUGS and have one question for your help. After running the following code, I got parameters of beta0 through beta4 (stats, density), but I don't know how to get the prediction of the last value of h, which I set to NA to model…
Bo Yu
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Is my OpenBUGS / WinBUGS model well specified?

I've just started trying to use OpenBUGS for Bayesian analysis of stochastic volatility models. In particular, I'm trying to calculate stochastic covariance, similar to the DC-MSV model specified by Meyer and Yu (2006). I found WinBUGS code online…
ch-pub
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7
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1 answer

Define Priors for Dirichlet Distribution parameters in JAGS

I'm defining a Multinomial-Dirichlet model in JAGS and want to assign some hyperpriors to the parameters of the Dirichlet distribution. In the WinBugs manual I read that "the parameters of Dirichlet and Wishart distributions and the order (N) of the…
user27115
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First iteration in MCMC coda chain is different from initial values

I have my jags output object. In order to understand how MCMC coda chains work, I tried to see if first iteration in each MCMC chain is equal to the initial values supplied. And it is different! The initial value is not there! Is it an error? Note…
Tomas
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2 answers

Thinning chains in BUGS/JAGS

Hi I have a quick question about the details of running a model in JAGS and BUGS. Say I run a model with n.burnin=5000, n.iter=5000 and thin=2. Does this mean that the program will run 5,000 iterations, and discard results, and then run…
user1375871
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Variables that do not converge in winbugs

I conducted a Bayesian analysis in winbugs and then checked the convergence from the history plots. The regression coefficients look stabilized, but the variance parameters don't. I got the number of iteration up to 5000, but it still does not look…
Günal
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CAR spatial models in JAGS

WinBUGS comes with the GeoBUGS add-on, which contains a number of predefined model structures that are suitable for modelling spatial data structures e.g. geostatical structures (spatial.exp), conditional auto-regressive, CAR, structures…
Mark Payne
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Logistic Regression - Bayesian Approach - Assessing Classification Accuracy

I have recently begun to read about bayesian statistics and I am playing around with the R2WinBUGS package. I'm trying to fit a logistic regression to the spam data (that can be found on the webpage of the elements of statistical learning) using R…
JEquihua
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Crazy divergence in mixed model - chains start well but go crazy later

I'm trying to compute a mixed model using jags (R2jags) and I got very strange divergence. The chains started so well, very well according to the results expected (also see lmer output of the same model below). But at certain point, the chains went…
Tomas
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Inferring multiple ratios and binomial proportions with missing data

I have a number of studies describing families tested for a genetic condition. For each study the following data are described: $n_p$, number of probands (the proband is the first person in a family to be diagnosed with the genetic condition, so…
tristan
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Can improper priors be implemented in some way?

I'm new to bayesian inference. I've just discovered that improper priors can't be specified in WinBUGS/OpenBUGS. I was wondering if this is common or not in bayesian inference. Are there same cases in which it's possible to implement a improper…
John M
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How can regression trees be fit in WinBUGS/OpenBUGS/JAGS?

There is an R package called BayesTree which can fit regression trees in Bayesian environment. However, this way only simple regression is possible. I would like to use regression trees as a part of a bigger hierarchical model instead of the simple…
Tomas
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