Displaying 20 results from an estimated 3000 matches similar to: "MCMC"
2005 Sep 23
4
books about MCMC to use MCMC R packages?
Dear list users,
I need to learn about MCMC methods, and since there are several packages in
R that deal with this subject, I want to use them.
I want to buy a book (or more than one, if necessary) that satisfies the
following requirements:
- it teaches well MCMC methods;
- it is easy to implement numerically the ideas of the book, and notation
and concepts are similar to the corresponding R
2007 Apr 03
1
Calculating DIC from MCMC output
Greetings all,
I'm a newcomer to Bayesian stats, and I'm trying to calculate the
Deviance Information Criterion "by hand" from some MCMC output.
However, having consulted several sources, I am left confused as to
the exact terms to use. The most common formula can be written as
DIC = 2*Mean(Deviance over the whole sampled posterior distribution)
- Deviance(Mean
2004 Feb 12
1
How do you create a "MCMC" object?
I have been running a Gibbs Sampler to estimate levels of efficiency in the
Louisiana Shrimp Industry. I created a matrix (samp) where I stored the
results of each iteration for 86 variables. I run 10,000 iterations. So, the
matrix samp is 10,000 x 86. I want to use the gelman-rubin test to check for
convergence. To do that, I need at least two chains. If I run second chain
with different starting
2005 Oct 28
1
MCMC in R
Dear R-helpers,
Hi! All.
I'm doing a project which needs MCMC simulation.
I wonder whether there exists related packages in R.
The only one I know is a MCMCpack package.
What I want to do is implementing gibbs sampling and
Metropolis-Hastings Algorithm to get the posterior
of hierarchical bayesian models.
Thanks in advance.
Jun
2006 Nov 16
2
Stochastic SEIR model
Dear colleagues,
I?m a new R-help user. I?ve read the advertisements about
the good manners and I hope to propose a good question.
I?m using R to build an epidemiological SEIR model based
on ODEs. The odesolve package is very useful to solve
deterministic ODE systems but I?d like to perform a
stochastic simulation based on Markov chain Montecarlo
methods. I don?t know which packages could be
2008 Jun 25
1
dgamma in WinBUGS and JAGS (rjags)
Hello,
In WinBUGS 1.4 manual
(http://www.mrc-bsu.cam.ac.uk/bugs/winbugs/manual14.pdf), the gamma
density is presented as dgamma(r,mu) where r and mu are the shape and
rate parameters, respectively. In JAGS (rjags) manual version 1.0.2,
May 9, 2008 (http://www-fis.iarc.fr/~martyn/software/jags/jags_user_manual.pdf),
on page 26 the gamma density is presented as dgamma(mu,r) instead of
dgamma(r,mu).
2004 Sep 15
3
getting started on Bayesian analysis
I am an economist who decided it's high time that I learned some
Bayesian statistics. I am following An Introduction to Modern
Bayesian Econometrics by T. Lancaster.
The book recommends using BUGS, but I wonder if there are any
alternatives which are free software and fully integrated to R (which
I have been using for more than two years for numerical computations.)
I would like to learn
2010 May 20
1
Geneland error on unix: Error in MCMC(........ :, unused argument(s) (ploidy = 2, genotypes = geno)
I am receiving the above error ( full r session output below) the
script runs OK in windows. and "genotypes" and "ploidy" are both
correct arguments
any suggestions would be most welcome
Nevil Amos
MERG/ACB
Monash University School of Biological Sciences
> library(Geneland)
Loading required package: RandomFields
Loading required package: fields
Loading required
2000 Apr 17
3
Maths in R documentation (PR#523)
The document R-exts contains the following example of using
mathematics in R documentation.
\deqn{p(x) = {\lambda^x\ \frac{e^{-\lambda}}{x!}}
{p(x) = lambda^x exp(-lambda)/x!}
There is a syntax error in there, but that's not my point.
The problem is that using "R CMD Rd2dvi" I find that putting
the alternate forms of the equation on top of each other doesn't
work.
2003 Apr 02
8
lm with an arbitrary number of terms
Hello folks,
Any ideas how to do this?
data.frame is a data frame with column names "x1",...,"xn"
y is a response variable of length dim(data.frame)[1]
I want to write a function
function(y, data.frame){
lm(y~x1+...+xn)
}
This would be easy if n was always the same.
If n is arbitrary how could I feed the x1+...+xn terms into lm(response~terms)?
Thanks
Richard
--
Dr.
1999 Jul 02
2
segfault on Sparc Linux (RH6.0)
We are having problems building R on Red Hat Linux 6.0/Sparc.
R compiles with no problem but then it fails "make tests".
Specifically, the line
eigen(cbind(-1,c(1:2,0),0:2)) # complex values
causes a segmentation fault. Previous versions of Red Hat Linux
did not give this problem.
The eigen() function is one of the rare cases in the base library where
Fortran code is called via the
2006 Jul 05
1
i suspect that there a memory leak in "vmmin"?
Dear listers,
Am currently using MCMC approaches to estimate some parameters of my model.
One parameter has to be updated using a tuned gamma distribution. So at each
iteration I estimate the mean and variance of the density of the gamma
approximation using "vmmin" (i also supply the gradient argument). For
moderate replications the procedure works, but if I increase them R crashes.
2001 Nov 29
1
R CMD check
I have been checking my package coda with the current R-devel
using "R CMD check". As usual, this has uncovered a large number
of errors and inconsistencies in my documentation, for which I
am very grateful.
The only problem I have is with code/documentation mismatches when I
have written a method for a generic function, e.g.
* checking for code/documentation mismatches ... WARNING
2011 Jan 19
2
MCMC object indexing
I have an mcmc object and I''m trying to plot the quantiles of the variables - and not as a function of the iterations as in cumuplot.
I cannot seem to find the right combination of indexing to access the variables; after which I''m sure I can plot all the statistics I could hope for.
Any hints for accessing the mcmc object would be appreciated.
=Dave
[[alternative HTML
2010 Apr 21
1
A question about plot.mcmc
Dear List members,
I am using R to generate MCMC time series plots.
This is the code I use; however, everytime an error message will come out
saying could not find function "plot.mcmc."
I have coda package and Lattice package installed.
Does anyone know what may get wrong here? Thanks so much for your
suggestions.
Hongli Li
*library (coda)
dat1=read.csv("Itemtime.csv")
2003 Aug 21
2
mcmc
Hello,
I am about to move all of my modelling work into R, and I have been
investigating the present state of MCMC and Bayesian methods in R.
Following a thread on the mailing list in 2000, I have looked at
mcmcpack and Hydra. Three years down the line, is there anything new in
this area? I have used both MCSim and WinBUGS in the past. The first one
seems promising, but is too focused towards
2001 Nov 29
1
R CMD check
[Sent to R-help by mistake. Sorry]
I have been checking my package coda with the current R-devel
using "R CMD check". As usual, this has uncovered a large number
of errors and inconsistencies in my documentation, for which I
am very grateful.
The only problem I have is with code/documentation mismatches when I
have written a method for a generic function, e.g.
* checking for
2018 Jan 18
2
MCMC Estimation for Four Parametric Logistic (4PL) Item Response Model
Good day Sir/Ma'am! This is Alyssa Fatmah S. Mastura taking up Master of
Science in Statistics at Mindanao State University-Iligan Institute
Technology (MSU-IIT), Philippines. I am currently working on my master's
thesis titled "Comparing the Three Estimation Methods for the Four
Parametric Logistic (4PL) Item Response Model". While I am looking for a
package about Markov chain
2006 May 11
1
about MCMC pack
Hello,
I tryed to use the MCMC pack, particularly the function MCMCirtKd to
simulate the posterior distribution in a multidimensional IRT model.
The code I used is:
posterior1 <- MCMCirtKd(Y, dimensions=2,
item.constraints=list("V2"=list(3,0)),
burnin = 1000, mcmc = 10000, thin=1, verbose = 1, seed = NA,
alphabeta.start = NA, b0 = 0, B0=0, store.item = FALSE,
2012 Dec 13
4
Running MCMC in R
Dear all
I am now running a MCMC iteration in the R program. But it is always
stucked in some loop. This cause big problems for my research. So I want to
know whether we can skip the current dataset and move to next simulated
data when the iteration is stucked? Alternatively, can the MCMC chain skip
the current iteration when it is stucked and automatically to start another
chain with different