similar to: sample a matrix with one element to be 1 from wishart distribution

Hello everyone I was wondering how would one simulate from a Normal Wishart Distribution in R. A normal inverted Wishart distribution is denoted by NIW (M,C,d,S), where X/(Sigma) ~ N( M,C,(Sigma) ) -> a matrix normal distribution, (Sigma) -> column dispersion matrix (Sigma) ~ IW (d,S) -> inverted Wishart distribution Thanks a lot ! Best Shantanu [[alternative HTML version

Hello Everyone Both the MCMCpack and the bayesm libraries allow us to make draws from the Inverse Wishart distribution. But I wanted to find out how exactly is the Inverse Wishart distribution parameterized in these libraries. The reason I ask is the following: Now its generally standard to express Inverse Wishart as IW(0.5 * DOF,0.5* Scale). (DOF-> Degree of freedom, Scale -> Scale

Hi, I'm using read.csv to import a table. But sevel columns are changed to factor variables automatically. They are actually numbers not factor levels. Why this happened? How can I get the correct table? Thanks a lot. Sonia [[alternative HTML version deleted]]

Dear R users, I am doing MCMC using Metropolis-Hastings. My model is bivariate-log-normal and the prior for variance-covariance is wishart distribution. I am wondering if there are some simple codes about how to get the density of Wishart distribution in my case ? Thanks in advance. Meihua [[alternative HTML version deleted]]

If so, I''ve had trouble finding it. Can anyone help?

Hi, guys, I am trying to sample from a truncated normal/gamma distribution. But only the far end of the distribution (where the probability is very low) is left. e.g. mu = - 4; sigma = 0.1; The distribution is Normal(mu,sigma^2) truncated on [0,+Inf]; How can I get a sample? I tried to use inverse CDF method, but got Inf as answers. Please help me out. Also, pls help me on the similar

Dear List, Is there any function in R to generate multivariate F distribution with given correlation/covariance matrix? Actually, I just want to generate some 2-dimentional non-normal data sets (skewed) for low (may be around 0.3 cor coeff.) negatively and also positively correlated variables ? Thanks in advance. Anna

hi i have a belkin ups here some setting chmod 0600 /dev/hiddev0 chown nut:root /dev/hiddev0 linux:/home/sonia # /usr/lib/ups/driver/upsdrvctl start Network UPS Tools - UPS driver controller 2.0.4 Network UPS Tools: New USB/HID UPS driver 0.28 (2.0.4) No matching USB/HID UPS found Driver failed to start (exit status=1) linux:/home/sonia # /usr/lib/ups/driver/upsdrvctl -u root start

Dear R-Representative: I am very new to R and I have to admit that I am not the cleverest of users. So, please bear with me. I have installed R on my Mac OS 8.6. I am interested in eventually using the packages -- many useful ones have been downloaded with the basic R software. I have looked through some of the manuals, however, I have not yet found how to access the commands in these packages.

Dear R users, I would like to make my R code for MCMC faster. It is possible to integrate C code into R but I think C is too complicated for me. I would need a C introduction only for MCMC and I do not know if such a thing exists. I was thinking of Python (and scipy). Where could I read about its integration into R ? How developed are the statistical packages in Python ? I could not find a

Hi Thanks for replying my question! What really interested me is that the package providing some complex form sampling, such as wishart, multinomial, dirichlet. And others for example conditional beta distribution confining the random variable in the interval (a, b). Since these concept are widely used in the baysian, I wonder whether somebody has already written this package. Thanks! Best

Hello, I have the following problem in installing a package (in windows xp) >rcmd install -c dlm [ ..stuff deleted ] ... DLL made installing DLL installing R files installing inst files installing data files installing man source files installing indices Errore in load(zfile, envir = envir) : l'input ?? stato danneggiato, LF sostituiti da CR Esecuzione interrotta

Hello, I have a dataframe of say 20 lines with one line per individual. I want to group these 20 individuals by length class (eg. of 5cm) and get the mean value of all the other variables (eg VarA and VarB) for each length class My dataframe is as follow: Length <- 10:30 VarA <- seq(1000,1200,10) VarB <- seq(500,700,10) Data <- cbind(Length,VarA,VarB) And I want to get something

R users- In moving from R 2.0.0 to R 2.1.0 in Windows, I have encountered a problem with the "riwish" command in the package "MCMCpack". I've searched the documentation and can't seem to figure it out. For example: Define a matrix: > lam <- matrix(c(.00233,-.00057,-.00057,.00190),2,2) and then use the riwish command to generate a random inverse-Wishart

I ne w in samba world but i was configured a Samba with shares folder linkable to users and it was successfull. Now i try to extend to PDC but the client can't logon into the server: the log.smbd could this [2009/06/12 15:51:21, 0] smbd/server.c:main(1209) smbd version 3.2.3 started. Copyright Andrew Tridgell and the Samba Team 1992-2008 [2009/06/12 15:51:21, 1]

I want to generate a valid variance-covariance matrix. One way could be to generate some random sample from multivariate normal distribution and then calculate cov. matrix. Another way could be to sample from wishart distribution itself. However both cases need a valid i.e. PD covariance matrix. As I need to generate that covariance matrix only, I am not interested those two methods. Can anyone

Respected R Users, I looking for help with generating theoretical confidence regions for any of non-symmetric bivariate statistical distributions (bivariate Chi-squared distribution<Wishart distribution>, bivariate F-distribution, or any of the others). I want to to used it as a benchmark to compare a few strategies constructing confidence regions for non-symmetric bivariate data. There is

I am just about to dive into Switchtower, but had a thought (go figure?). Could Switchtower use be inverted? Could user, clients, or customers install switchtower and "pull" applications? Just a thought. -- Posted via http://www.ruby-forum.com/.

What is the best way to search a (possibly long) string of free-form text (like, say, an email) for occurrances of some set of key phrases of interest? Fuzzy or not; I''ll take what I can get. Thanks in advance! -- Sonia Lyris | slyris at gmail.com

Dear useRs, I have written a function that implements a Bayesian method to compare a patient's score on two tasks with that of a small control group, as described in Crawford, J. and Garthwaite, P. (2007). Comparison of a single case to a control or normative sample in neuropsychology: Development of a bayesian approach. Cognitive Neuropsychology, 24(4):343?372. The function (see