similar to: multivariate F distribution

Hello, I have a question about multivariate Shapiro-Wilks test. I tried to analyze if the data I have are multivariate normal, or how far they are from being multivariate normal. However, any time I did >mshapiro.test(mydata) I get the message: Error in solve.default(R %*% t(R), tol = 1e-18) : system is computationally singular: reciprocal condition number = 5.38814e-021 I tried

Dear List, I would like to ask about package RGtk2 with which I have a problem. I will very much appreciate if somebody could tell me what I need to do. I need to install a package scdMicro and it depends on gWidgetsRGtk2. I am working on MAC, version 10.5.8. When I try to load gWidgetsRGtk2 (or RGtk2), it asks me: "Instal GTK+?" I installed Gtk+ from CRAN, and added a path: export

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

Dear All, Is there any function in R for computing "multivariate chi-square distribution"? How about "multivariate gamma distribution"? I appreciate any comment on this subject. Thank you, Amin Zollanvari PhD student Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX

Hi All. I have a mysql statement that I would really really like to call from my Ruby program which goes like this: SELECT a, b, DAYOFWEEK(date_time) as DOW, HOUR(date_time) at hr, AVG(x/y) FROM records; This is possible by creating a 3-dimentional array of a, b, date_time containing x/y, and then finding averages and putting it into a 4-dimensional array of a, b, dow,

Dear all R users, I am wondering if there is any way to define a 3 dimentional or 4 dimentional array in R. Sincerely yours, thanks in advance Send instant messages to your online friends http://in.messenger.yahoo.com Stay connected with your friends even when away from PC. Link: http://in.mobile.yahoo.com/new/messenger/ [[alternative HTML version deleted]]

Hi, I need to do several matrix multiplications with the corresponding matrices forming two 3-dimentional arrays. To illustrate my problem, let's say I have the following 3-dimensional arrays: array1 <- array(1:30,dim=c(3,2,5)) array2 <- array(1:20,dim=c(2,2,5)) I know that I can get what I want with the following computation : result <- array(dim=c(dim(array1)[1],

Dear R users I have the matrix of the centres of some clusters, e.g. 20 clusters each with 100 dimentions, so this matrix contains 20 rows * 100 columns numeric values. I have collected new data (each with 100 numeric values) and would like to keep the above 20 centres fixed/'unmoved' whilst just see how my new data fit in this grouping system, e.g. if the data is close to cluster 1

Art (and group), I'm doing this as a form of missing value analysis. Approximately 30% of the cases are missing data for one variable. To impute values for those cases, I'd like to match those cases that are missing the variable to all other cases and then take an average of those to infill. I realize there are many methods for imputing data. I'm not well versed on any in

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

This should be simple but I am struggling. I like to easily switch in xyplot between a linear or logarithmic y-axis by setting a logical flag logY to False or True. This switch changes the scales argument of xyplot. I found out that the original two-dimentional data (Conc vs Time in my case) are converted to log10(Conc) if log=TRUE in scales, but it appears that functions like panel.curve need to

Hi; I have a very basic question about reading element from dataframe T (2 dimentional) I want to extract element T[1,1] as a string. T[1,1] returns an element with "names", means header. this i cannot compare with any other list of strings. how can i fix that? Thanks Rami _________________________________________________________________ [[alternative HTML version

Hi; I have a very basic question about reading element from dataframe T (2 dimentional) I want to extract element T[1,1] as a string. T[1,1] returns an element with "names", means header. this i cannot compare with any other list of strings. how can i fix that? Thanks Rami _________________________________________________________________ Get back to school stuff for them and

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

Dear List, How can I convert a list with elements being character strings, like: "c(1,2,3,4)", ?c(1,3,4,2) ? to a list with elements as numerical vectors: c(1,2,3,4), c(1,3,4,2)?? Thanks! Anna

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

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]]

Hi, This is a very simple question I realise, but I hope maybe someone can just help me out. I am trying to do a very simple thing, just transfer a file from machine A to machine B using rsync with ssh. This is what i'm typing: bash-2.03# rsync -avvv --rsh="ssh -l tdf" tdf@machine.niss.ac.uk:/export/home/tdf/demofile.html demofile.html This is what I get: opening connection

Hello, Is there any possibility in R to see the body of the non-visible function, for example princomp? If I do : > methods(princomp) so, I get that princomp.default and princomp.formula are non-visible functions and body(princomp.default) doesnt show it. In particular, I guess I have a very nave question Id like to see how scores calculation is implemented in the function princomp.

Hi, I am not sure if this make sense at all. I'd like to sample a matrix, which follows a wishart / inverted wishart distribution. However, the (1,1) element of this matrix should always be equal to 1. How can I handle it in R? Any suggestion is greatly appreciated. Thanks a lot. Sonia [[alternative HTML version deleted]]