Displaying 20 results from an estimated 4000 matches similar to: "MCMC object indexing"
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")
2008 Jun 30
1
Coda not providing summary on mcmc object
The object is a mcmc sample from lmer. I am using R v2.7.1. Please let me
know what additional information I can provide, hopefully I am just making a
simple mistake. Thanks in advance!
> data(ratdrink, package = 'faraway')
> rd.er <- lmer(wt ~ weeks*treat + (1 | subject), data = ratdrink)
> rd.mc <- mcmcsamp(rd.er, 10000)
> library(coda)
Loading required package:
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
2010 Apr 26
2
Unexpected warnings from summary() on mcmc.list objects
I am trying to get summary statistics from WinBUGS/JAGS output in the
form of mcmc.list objects, using the summary() function. However, I
get odd warning messages:
Warning messages:
1: In glm.fit(x = X, y = Y, weights = weights, start = start, etastart
= etastart, :
algorithm did not converge
2: In glm.fit(x = X, y = Y, weights = weights, start = start, etastart
= etastart, :
algorithm did
2007 Mar 09
1
MCMC logit
Hi,
I have a dataset with the binary outcome Y(0,1) and 4 covariates (X1,X@,X#,X$). I am trying to use MCMClogit to model logistic regression using MCMC. I am getting an error where it doesnt identify the covariates ,although its reading in correctly. The dataset is a sample of actual dataset. Below is my code:
> #######################
>
>
> #retreive data
> # considering four
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,
2011 Feb 24
2
MCMCpack combining chains
Deal all, as MCMClogit does not allow for the specification of several chains, I have run my model 3 times with different random number seeds and differently dispersed multivariate normal priors.
For example:
res1 = MCMClogit(y~x,b0=0,B0=0.001,data=mydat, burnin=500, mcmc=5500, seed=1234, thin=5)
res2 = MCMClogit(y~x,b0=1,B0=0.01,data=mydat, burnin=500, mcmc=5500, seed=5678, thin=5)
res3 =
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
2007 Mar 12
2
Lmer Mcmc Summary and p values
Dear R users
I am trying to obtain p-values for (quasi)poisson lmer models, including
Markov-chain Monte Carlo sampling and the command summary.
>
> My problems is that p values derived from both these methods are
totally different. My question is
(1) there a bug in my code and
>
(2) How can I proceed, left with these uncertainties in the estimations of
> the p-values?
>
> Below
2005 Sep 27
1
About Coda Package
Dear R users:
I am using the package coda (the last verison in CRAN) to analyse the output from a MCMC Bayesian analysis. And I get unconsitented results. I have export the chain using the read.table function and after I have transformed this data frame to an mcmc object using the mcmc function. I am interested in three variables, when I use the function effectiveSize I have these figures:
2013 Mar 28
3
problem with plots with short example.
i am having problem running my own data. yesterday it was working just fine. today it is not. this is the code i was using as an example to follow. this code ALSO worked just fine yesterday, and is no longer working at all. i suspect it is a problem with either my computer or the software, at this point. if THIS won't even run.... something is wrong.
i can assure you this isn't
2004 Oct 31
2
Error Message: MCMCpack and coda
Hello All,
I'm trying to run a one-dimenional irt model using the packages MCMC and
coda on a rather large set of roll-call voting data with many missing
observations. Here's a sample of the code:
Post10<-
MCMCirt1d (Italy10, burnin = 1000, mcmc=50000, thin=100, verbose=TRUE,
theta.constraints = list(V549=1, V443=-1))
The MCMCirt1d command seems to work fine, but when I try to
2012 Jun 05
1
load coda in BRugs to perfor diagnostics
Dear all,
I just wrote a script to have each of my three mcmc chins running on a
different computer core to improve computation speed. To do it I use the
function sfLapply from the package snowfall.
Before using parallell computation, I did my diagnostic analyses just after
the model updating, but now I have to save the coda before.
Using the CODA package, it is possible to load the outputs in a
2009 Oct 06
2
R, Coda, and OpenBUGS
Hi All,
I am trying to figure out how to use R-Coda with the output from
OpenBugs. I have installed and loaded the packages BRugs and R2WinBUGS.
I have successfully run a simple Bayes model in WinBUGS using R2WinBUGS'
"bugs" and have used "read.bugs" to build the coda object. I can
successfully switch to OpenBugs and run the same model and get the basic
summary
2010 Nov 07
3
Computing ergodic mean with CODA
Hi all,
I would like to compute ergodic mean using MCMC output from WinBUGS. I
tried using CODA package, but it seems that it is not implemented yet.
Could anyone help me to compute this? Attached to this email are my
output and index files.
Kind regards,
Raquel
--
Raquel Rangel de Meireles Guimar?es
Doutoranda em Demografia
raquel at cedeplar.ufmg.br
2012 Oct 04
1
Coda, HPDinterval and multiple chains
Dear all,
I'm not 100% sure if this question is best directed at the r-list, or a mailing list concerned with Bayesian analysis, so please accept my apologies if another audience may be more appropriate.
I have been using the rjags package to run Jags models with multiple chains and store the results in a Coda based mcmc list. For instance, having created a jags model and done initial
2010 Mar 28
3
Ellipse that Contains 95% of the Observed Data
I can take the results of a simulation with one random variable and generate
an empirical interval that contains 95% of the observations, e.g.,
x <- rnorm(10000)
quantile(x,probs=c(0.025,0.975))
Is there an R function that can take the results from two random variables
and generate an empirical ellipse that contains 95% of the observations,
e.g.,
x <- rnorm(10000)
y <- rnorm(10000)
?
2007 Aug 21
1
small issue with densityplot
Hi folks,
This is really minor but to someone not familiar with the various tentacles of the lmer package it could be really annoying. I was trying to plot the posterior density of the fixed effect parameters of a lmer model,
> hr.mcmc = mcmcsamp(hr.lmer, n=50000)
> densityplot(hr.mcmc, plot.points=F)
There is this error,
"Error in densityplot(hr.mcmc, plot.points = F) :
no
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.
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