Displaying 20 results from an estimated 1000 matches similar to: "Where is package "Umacs"?"
2007 Oct 31
1
Simple Umacs example help..
Hello all...
I am just starting to teach myself Bayesian methods, and am
interested in learning how to use UMacs. I've read the
documentation, but the single example is a bit over my head at the
level I am at right now. I was wondering if anyone has any simple
examples they'd like to share. I've successfully done a couple of
simple gibbs examples, but have had a hard time
2009 Aug 17
1
Bayesian data analysis - help with sampler function
I have downloaded the Umacs (Universal Markov chain sampler) and submitted the following sample code from Kerman and Gelman.
s <-Sampler(
J=8,
sigma.y =c(15,10,16,11,9,11,10,18),
y =c(28, 8,-3,7,-1,1,18,12),
theta =Gibbs(theta.update,theta.init),
V =Gibbs(V.update,mu.init),
mu =Gibbs(mu.update,mu.init),
tau =Gibbs(tau.update,tau.init),
2009 Feb 17
1
Cross classified or Multiple membership or Hierarchical (3 level ) logistic models using Umacs
Dear R users,
I would like to fit cross classified or multiple membership logistic models
or a 3 level hierarchical logistic model using the Umacs package. Can anyone
advise me on how to proceed or better point me to examples of how its done.
Regards,
--
Luwis Diya,
Leuven Biostatistics and Statistical Bioinformatics Centre (L-BioStat),
Kapucijnenvoer 35 blok d - bus 7001,
3000 Leuven,
2008 Jun 22
3
R vs. Bugs
A naive question from a non-statistician: I'm looking into running a
Bayesian analysis of a model with high dimensionality. It's not a
standard model (the likelihood requires a lot of code to implement),
and I'm using a Linux machine. Was wondering if someone
has any thoughts on what the advantages of OpenBugs are as
opposed to just R (or should I be thinking WinBUGS under Wine?)?
2006 Aug 11
2
about MCMC pack again...
Hello, thank you very much for your previous answers about the C++ code.
I am interested in the application of the Gibbs Sampler in the IRT
models, so in the function MCMCirt1d and MCMCirtkd. I've found the C++
source codes, as you suggested, but I cannot find anything about the
Gibbs Sampler. All the files are for the Metropolis algorithm.
Maybe I am not able to read them very well, by the
2008 Apr 08
2
Metropolis acceptance rates
Is there a way to recover Metropolis-step acceptance rates AFTER
completing posterior draws?
The immediate application is in the probit.bayes and logit.bayes
models used by Zelig... which I believe is merely calling MCMCpack.
So one strategy, to which I am fixing to resort, is to call, say,
MCMClogit with verbose set to mcmc (or mcmc divided by an integer)
and then look at my screen.
2007 Mar 01
1
LDAP error
Hi,
When i try to inser this on LDAP database, i get this error:
"ldapadd: invalid format (line 14) entry:
"uid=spessoa,ou=users,ou=accounts,dc=telbit,dc=pt""
I can't see nothing wrong.
The .ldif file follows my signature.
Any help would be appreciated.
Warm Regards,
M?rio Gamito
--
dn: dc=telbit,dc=pt
objectClass: top
objectClass: dcObject
objectClass: organization
o:
2007 Jun 06
1
Metropolis-Hastings Markov Chain Monte Carlo in Spatstat
I'm testing some different formulations of pairwise interaction point processes
in Spatstat (version 1.11-6) using R 2.5.0 on a Windows platform and I wish to
simulate them using the Metropolis-Hastings algorithm implemented with Spatstat.
Spatstat utilizes Fortran77 code with the preprocessor RatFor to do the
Metropolis-Hastings MCMC, but the Makefile is more complicated than any I have
2009 Aug 12
1
MCMC sampling question
Hello,
Consider MCMC sampling with metropolis / metropolis hastings proposals
and a density function with a given valid parameter space. How are MCMC
proposals performed if the parameter could be located at the very
extreme of the parameter space, or even 'beyond that' ? Example to
express it and my very nontechnical 'beyond that': The von Mises
distribution is a circular
2005 Jul 19
1
initial points for arms in package HI
Dear R-users
I have a problem choosing initial points for the function arms()
in the package HI
I intend to implement a Gibbs sampler and one of my conditional
distributions is nonstandard and not logconcave.
Therefore I'd like to use arms.
But there seem to be a strong influence of the initial point
y.start. To show the effect I constructed a demonstration
example. It is reproducible
2007 Jan 30
2
R packages
Hi,
Do any body know which packages of R I need to go for the below topics?
1. Monte Carlo Markov chain (MCMC)
2. Gibbs Sampling
3. Metropolis Hastings
Thanks in advance...
Shubha
[[alternative HTML version deleted]]
2007 Dec 04
1
Metropolis-Hastings within Gibbs coding error
Dear list,
After running for a while, it crashes and gives the following error message: can anybody suggest how to deal with this?
Error in if (ratio0[i] < log(runif(1))) { :
missing value where TRUE/FALSE needed
################### original program ########
p2 <- function (Nsim=1000){
x<- c(0.301,0,-0.301,-0.602,-0.903,-1.208, -1.309,-1.807,-2.108,-2.71) # logdose
2012 Nov 30
1
Example metropolis hasting
Hello all, could you tell where is an example of metropolis hasting?
Thank you!
Tania
Sent from my iPod
2012 Aug 05
1
Possible bug with MCMCpack metropolis sampler
Hi,
I'm having issues with what I believe is a bug in the MCMCpack's
MCMCmetrop1R function. I have code that basically looks like this:
posterior.sampler <- function(data, prior.mu){
log.posterior <- function(theta) log.likelihood(data, theta) +
log.prior(prior.mu, theta)
post.samples <- MCMCmetrop1R(log.posterior, theta.init=prior.mu,
burnin=100, mcmc=1000, thin=40,
2008 May 12
4
Several questions about MCMClogit
Hello everybody,
I'm new to MCMClogit. I'm trying to use MCMClogit to fit a logistic
regression model but I got some warnings I can't understand.
My input data X is 32(tissue sample)*20(genes) matrix, each element in this
matrix corresponds to the expression value of one particular gene in one of
32 samples. And the Y presents the corresponding classes (0-non cancer,
1-cancer)
2007 Mar 02
1
Help with faster optimization for large parameter problem
Hello all,
I have a large parameter problem with the following very simple likelihood
function:
fn<-function(param) {
x1<-param[1:n]
g1<-param[(n+1):(2*n)]
beta<-param[(2*n+1):(2*n+k)]
sigma2<-param[2*n+k+1]^2
meang1sp<-mean(g1[sp])
mu<-beta%*%matrix(x1,1,n)-(g1[sp]-meang1sp)%*%matrix(g1,1,n)
return(sum((ydc-mu)^2)/(2*sigma2) + n*k*log(sqrt(sigma2)) +
2005 May 01
2
eigen() may fail for some symmetric matrices, affects mvrnorm()
Hi all,
Recently our statistics students noticed that their Gibbs samplers were
crashing due to some NaNs in some parameters. The NaNs came from
mvrnorm (Ripley & Venables' MASS package multivariate normal sampling
function) and with some more investigation it turned out that they were
generated by function eigen, the eigenvalue computing function. The
problem did not seem to happen
2013 Mar 01
2
using reserved words in R, and reuse variable names in different functions
Hi list,
I am writing several functions and running out variable names. I am using
words such as "t", "c", "matrix" to keep the notation same as formulas I am
using.
For example I have,
unnormalized <- function(t, x, y){
val <- rnorm(t, mean=x, var=y)
return(val)
}
metropolis <- function(t, c, x, y){
den1 <- unnormalized(t, mean=x, sd=y)
2009 Nov 08
3
MCMC gradually slows down
Hello,
I have written a simple Metropolis-Hastings MCMC algorithm for a
binomial parameter:
MHastings = function(n,p0,d){
theta = c()
theta[1] = p0
t =1
while(t<=n){
phi = log(theta[t]/(1-theta[t]))
phisim = phi + rnorm(1,0,d)
thetasim = exp(phisim)/(1+exp(phisim))
r = (thetasim)^4*(1-thetasim)^8/(theta[t]^4*(1-theta[t])^8)
if(runif(1,0,1)<r){
theta[t+1] = thetasim
}
2016 Nov 03
6
CTDB and locking issues in 4.4.6 (Classic domain)
On 03/11/16 19:37, Volker Lendecke wrote:
> On Thu, Nov 03, 2016 at 07:11:12PM +0000, Alex Crow via samba wrote:
>>
>> On 03/11/16 14:28, Ralph Böhme wrote:
>>>> Ah, my smb.conf is missing the "ctdb socket" parameter. According to "man
>>>> smb.conf" this should be set, but I don't remember seeing it on the wiki
>>>> pages.