Questions tagged [mcmc-acceptance-rate]

The acceptance rate (acceptance ratio, acceptance fraction) for a Markov Chain Monte Carlo sampler indicates the fraction of accepted over proposed moves.

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Jacobian term for Metropolis Hastings algorithm?

Suppose an acceptance ratio of the MH sampler without parameter transformation is like this: \begin{gather} r=\frac{f( \theta ',\gamma '|y,m) q( \theta ',\gamma '|\theta ,\gamma )}{f( \theta ,\gamma |...
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Adaptive MCMC with low acceptance rate

I'm running an MCMC scheme defined in A tutorial on adaptive MCMC. Christophe Andrieu·Johannes Thoms. Stat Comput (2008) 18: 343–373DOI 10.1007/s11222-008-9110-y. They say the optimal scaling factor ...
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Simulated annealing acceptance probability puzzle

My understanding of simulated annealing (SA) is that at any iteration $t$, a new sample $Y_t$ is generated, which, if the objective function $E$ is improved, i.e., $E(Y_t)<E(X_{t-1})$, then $Y_t$ ...
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How do we need to define the acceptance ratio of the Metropolis-Hastings algorithm for a vanishing proposal density?

I've seen that different authors define the acceptance probability $\alpha$ of the Metropolis-Hastings algorithm with target distribution density $p$ and proposal kernel density $q$ differently; some ...
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How do I account for numerical overflow with Adaptive MCMC?

EDIT: I tested Forgottenscience's solution below and it works; however, note that I found the working acceptance criterion to be that if $\log\alpha \geq \log u$, the point is accepted, where $u\sim\...
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Do I need to evaluate acceptance rates in Metropolis within Gibbs algorithm?

Consider the Gibbs sampler Sample $\theta' \sim p(\theta|\tau, D)$ Sample $\tau' \sim p(\tau|\theta', D)$ where $\theta,\tau$ parameters of the data $D$. Now assume that we can only sample from $p(\...
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Can a Metropolis-Hastings estimator converge if the proposal density vanishes whenver the target density vanishes?

I'm running the Metropolis-Hastings algorithm for a target and proposal density $p$ and $q$, respectively, for which it holds $$p(y)=0\Rightarrow q(x,y)=0\;\;\;\text{for all }y.\tag1$$ By definition ...
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Erroneous expression for Metropolis-Hastings acceptance ratio in a paper

Let $(E,\mathcal E)$ be a measure space; $\rho:E\to[0,\infty)$ be $\mathcal E$-measurable, $p:E^2\to[0,\infty)$ be $\mathcal E^{\otimes2}$-measurable, $$r(x,y):=\left.\begin{cases}\displaystyle\frac{\...
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Need to understand a statement for Random Walk Metropolis algorithm's proposal distribution?

I was told that the proposal distribution of Random Walk Metropolis needs to be symmetric. But today I was reading a book about Bayesian Analysis which contains the following statement: "The proposal ...
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How to tune MCMC with unwieldy posterior [duplicate]

Let's say I have $n$ observations of a random variable, $X_1, \dotsm, X_n \sim \mathcal{N}(0, \sigma^2)$. I also assume $\sigma^2$ has a Gamma(1,1) prior distribution, $\pi(x) = \exp(-x)$. I'm now ...
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Hamiltonian Monte Carlo with acceptance threshold of zero

I realize this is an open-ended question, but I'll accept any answer with gives a reasonable explanation and something to try. I'm running Hamiltonian Monte Carlo, specially pyhmc, and logging the ...
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Adaptive MCMC when variables exist only conditionally?

I'm looking at models that make the existence of one variable depend on another variable. For example, n ~ geometric(0.5) x ~ iid(n,normal(0,1)) Here, ...
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convergence and efficiency of mcmc chains and estimation of covariance matrix

I am doing some bayesian analysis and exploring posterior distribution with mcmc method. I would like some clarification with estimating the covariance matrix. I have a model with 6 parameters. ...
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Expression for the mean acceptance rate of the Metropolis-Hastings algorithm

Let $(E,\mathcal E,\lambda)$ be a measure space $p:E\to[0,\infty)$ be $\mathcal E$-measurable with $$c:=\int p\:{\rm d}\lambda\in(0,\infty)$$ and $$\mu:=\underbrace{\frac1cp}_{=:\:\tilde p}\lambda$$ $...
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MCMC Metropolis-Hastings sampler - Estimation of multiple parameters

First time that I ask a question on this platform! Here I go... I have a dataset with two random variables X1 and X2 and an output Y which comes from a discrete Weibull distribution. I've been trying ...
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How to evaluate the draw from the proposal of a Metropolis-Hastings?

In the Metropolis-Hastings step of a MCMC, given a $\theta_n$, I'm drawing $\theta_{n+1} \sim F(\mu(\theta_n), \Sigma)$ where the $\mu $ is a location vector and $\Sigma$ is a scale matrix. When ...
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Why volume preservation is important for Metropolis update? [duplicate]

I think my question is naive but I would like to ask why why volume preservation is important for MCMC and specifically Metropolis update.I'm reading the following paper https://arxiv.org/pdf/1206....
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How does the celebrated result about the diffusion limit of the Random Walk Metroplis-Hastings algorithm help us to find the optimal scaling

Let $d\in\mathbb N$ with $d>1$ $\ell>0$ $\sigma_d^2:=\frac{\ell^2}{d-1}$ $f\in C^2(\mathbb R)$ be positive with $$\int f(x)\:{\rm d}x=1$$ and $g:=\ln f$ $Q_d$ be a Markov kernel on $(\mathbb R^...
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Proposal in MCMC lives in bigger space than parameter space. Which transformations should I choose?

I'm using a MCMC algorithm. The proposal is, due to lack of information on my part, a multivariate T-Student distribution, i.e. $\theta \sim \mathcal{MT}(\mu, \Sigma)$. However, some of the components ...
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Is the MC produced by HMC reversible?

I know that the deterministic dynamics in Hamiltonian Monte Carlo/Hybrid Monte Carlo are reversible and the numerical integrators one uses to approximate them are reversible too. But HMC consists of 2 ...
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2 versions of Metropolis-Hastings : are they equivalent?

I have seen 2 different versions of Metropolis algorithm. First one : Second one : I don't understand the differences between the 2 versions, especially in the second one where I have to use the ...
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Metropolis Hastings - Acceptance ratio, proposal and lkelihood

From a previous post : First to explain the MH algorithm, it's used to approximate numerically a target distribution, in this case $p(\theta|D)$. At each stage of the algorithm: A value ...
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How worried should I be about low acceptance rate in cold chain (parallel tempering MCMC sampler)

I have a very noisy/multimodal likelihood function for a 6-parameter model. The popular emcee sampler fails miserably (no matter how many chains I use and for how ...