# Questions tagged [gibbs]

The Gibbs sampler is a simple form of Markov Chain Monte Carlo simulation, widely used in Bayesian statistics, based on sampling from full conditional distributions for each variable or group of variables. The name comes from the method being first used on Gibbs random fields modeling of images by Geman and Geman (1984).

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### Why does Slice sampler use the log of the density?

The Slice sampler1 takes as its argument the log of the density to be sampled from. Why is it doing this? A commenter on this question pointed out that it makes no sense to "sample" from the log of ...
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### Gibbs sampling from full conditionals

I have the following joint density: $p(x_1,x_2,y_1,y_2) \propto \exp\left(−\left(x_1^2+x_2^2+c_1(y_2-y_1)^2+c_2(y_2-y_1)^4\right)\right)$ Can I use Gibbs sampling to sample from that? How can I get ...
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### Canonical example to understand Gibbs Sampling

I'm been trying to understand Gibbs sampling. What I'm looking for is a paper or other reference which uses a simple canonical example and uses that to illustrate Gibbs sampling. Sadly I've not ...
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### Sampling variables and calculating likelihood in WinBUGS/OpenBUGS

I am trying to read some WinBUGS/OpenBUGS examples to figure out how to specify models. I can't seem to understand where the probabilistic dnorm, ...
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### Gibbs sampling and Bayesian inference

I wanted to get a more in-depth understanding of sampling algorithms, and so I thought I could start with the very simple example of a binomial or bernoulli likelihood with a beta prior (since it is ...
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### Gibbs sampling convergence

In an astronomical context, the authors of a paper desire to use a Gibbs algorithm. Please note: I am inexperience in MCMC algorithms, and specifically in Gibbs sampling. What we want, in essence, is ...
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### Gibbs sampling and Conjugate Priors

Are conjugate priors required when performing Gibbs sampling?
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### JAGS: posterior predictive distribution

I am fitting a simple linear regression model with R & JAGS: ...
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### What's the role of the data in Gibbs Sampling?

Trying to wrap my mind around Gibbs Sampling. Across many answers in this same forum, I constantly notice that the examples shown do not actually require an observed data set (First example (with R ...
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### What is a hierarchical model that can estimated via the Metropolis-Hastings Algorithm but not the Gibbs Sampler?

My understanding of the differences between MH and Gibbs Samplers is that a Gibbs Sampler is usually used when the full conditionals are present to us. In other words, it is a known distribution, so ...
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### Markov Chain Monte Carlo (MCMC) with transformed data

I want to obtain an estimate of a parameter $\Theta$ in a model for a random variable $X$ dependent on $\Theta$ with known but complicated likelihood $L(\Theta|X) = p(X|\Theta)$. $X$ is not directly ...
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### Gibbs sampling with mixed prior using a Metropolis-Hastings step

My questions are about a sampling procedure for ﬁtting a Bayesian hierarchical model where one of the priors is a mixture distribution of discrete and continuous parts. The model is not my own but I ...
### Slice Sampling asks to draw from $f^{-1}]y,+\infty[$
Slice Sampling asks to draw uniformly from $f^{-1}]y,+\infty[$. Wikipedia page However, how can we be sure that a uniform defined over the set $f^{-1}]y,+\infty[$ is in fact proper? If I had to ...