similar to: Re : Information

To whom it may concern, I try to simulate a non-normal multivariate distribution. The MASS package allows by mean of "mvrnorm" command to perform a multivariate normal simulation. Is there an equivalent command for an arbitrary multivariate distribution available in the R-language? Thank you in advance. Bernard Colin Colin Bernard Professeur titulaire D?partement de Math?matiques et

Hello, In my simulations, I have to use the values of the cumulative distribution function of a multivariate normal with known mean vector and dispersion matrix. Please, can you tell me if there is a package in R to do that? Thank you very much for your greatly appreciate cooperation. Bernard Colin Colin Bernard Professeur titulaire Département de Mathématiques Faculté des Sciences Université

Howdee, One of my student spotted something I can't explain: a probability >1 vs a normal probability density function. > dnorm(x=1, mean=1, sd=0.4) [1] 0.9973557 > dnorm(x=1, mean=1, sd=0.39) [1] 1.022929 > dnorm(x=1, mean=1, sd=0.3) [1] 1.329808 > dnorm(x=1, mean=1, sd=0.1) [1] 3.989423 > dnorm(x=1, mean=1, sd=0.01) [1] 39.89423 > dnorm(x=1, mean=1, sd=0.001) [1]

Howdee, *** I know that the lmList() function exists, yet I don't want to use it. *** Would anyone be kind enough to tell how I can apply the function lm() to each level of a given factor so to obtain the intercept and slope for each factor level within a matrix? For instance, suppose a dataframe containing 3 variables: id, x and y. I want to compute the function lm() for each level

Howdee, My question appears at #6 below: 1. I want to model the growth of each of a large number of individuals using a 4-parameter logistic growth curve. 2. nlme does not converge with the random structure that I want to use. 3. nlsList does not converge for some individuals. 4. I decided to go around nlsList using: t(sapply(split(data, list(data$id)), function(subd){coef(nls(mass ~

Howdee, I am able to fit a 4-parameter logistic growth curve to a dataset which comprise many individuals (using R v. 2.3.1). Yet, if I want to obtain the parameters for each individual (i.e., for each 'id') using nlsList, then I obtain an Error message which I have trouble interpreting. Any advice as to how I can solve this problem? Thanks for your time, Marc > reg <-nls(mass ~

Hi there, I have 3 numeric variables: day (e.g., 05), month (e.g., 06), year (e.g., 2009). I would like to create a (string) variable of the following form: month/day/year (e.g., 06/05/2009). I would be grateful to anyone who could point me toward a solution. Sincerely, Marc =================== Marc B?lisle Professeur agr?g? Chaire de recherche du Canada en ?cologie spatiale et en ?cologie

Is there a way to apply a function, say cor(), to each combination of some number of variables, and this, without using loops? For example, I have day, hour, var1 and var2. How could I compute cor(var1,var2) for each day*hour combination and obtain a matrix with day, hour and the cor value for each combination? Thanks for your time, Marc =================== Marc Bélisle Professeur adjoint

How do one dertermine the optimal number of rescaling cycles to use when performing DCA using the decorana function (library vegan)? Thanks for your time, Marc =================== Marc Bélisle Professeur adjoint Chaire de recherche du Canada en écologie spatiale et en écologie du paysage Département de biologie Université de Sherbrooke 2500 Boul. de l'Université Sherbrooke, Québec J1K 2R1

In trying to change the driver used by Sweave on the command line using R CMD Sweave --driver=foo I consistently get the "directory 'foo' does not exist' error. (For any value of 'foo', even the default 'RweaveLatex'.) Looking up the source code for function .Sweave that is called by 'R CMD Sweave', I notice that the argument 'driver', if

Trust me or not, I solve all my browsing problem doing this: hosts allow = 193.190.195.64/255.255.255.192 193.190.195.32/255.255.255.224 193.190.194.0/255.255.255.0 193.190.192.0/255.255.255.0 localhost ;!!!!! interfaces = 193.190.195.69/255.255.255.192 ;!!!!! ;remote announce = Before adding interfaces, just the browsing in the first subnet was OK! I'm running Samba 1.9.16p11 on AIX

Dear R-users, using the interactive mode, the command > summary(my.survreg.object) will output details of the object my.survreg.object in a very neat fashion. I would like to have that sent to a file, in ascii format, as it appears within the interactive mode. Is that possible ? This seems like a very simple task, but i haven't found the solution: - print doesn't care about a file

I'm just getting started with R, having a lot of original work on modeling and exploring the simulation by MCMC. I want to simulate the prior and the posterior distribution of Dirichlet Process by MCMC. Is there anyone in NYC that might be a good tutor for me? -- Dr. P. NGOM, Facult? des Sciences et Techniques D?partement de Math?matiques et Informatique Universit? Cheikh Anta Diop Dakar -

I look for codes sources of R (examples of application) to implement examples on Monte Carlo, MCMC and Gibbs sampling. -- Dr. P. NGOM, Facult? des Sciences et Techniques D?partement de Math?matiques et Informatique Universit? Cheikh Anta Diop Dakar - S?n?gal ---------------------------------------------------------------- Universite Cheikh Anta DIOP - DAKAR

Hi , I'm currently trying to make available a few fortran subroutines and R functions (which make interface to these subroutines), as an R package. I'm doing it under linux with R 1.9.0 (but hope to do it for windows too). I have trouble for loading my fortran code. Here are the steps involved : 1) In R: # Create tree for package

I want to specify a 2-level mixed model using the lme function in order to test an a priori hypothesis about the between-group values of the slopes but don't know how to do this . Here is the problem. Consider first the case of a single group. The model is: Y_i= a +bX_i + error where I indexes the different values of X and Y in this group . The a priori hypothesis of the slope is: b=K.

Hi, I'm just getting started with R and I'm having problems with some simple operations: I want to get the the sum of the column "SStot" for each year using the function by. The data set is named "SS". I've tried this: by (SS, year, sum(SStot)) and it's not working. Is it because there's a different number of rows for each year? How else can I do

Hi list! I did the following regression: reg1 <- glm(alti~sp + ovent + vivent + nuage, family=gaussian, data=meteo1) I was interested in knowing the effect of the species (sp) in reg1 and so I used the function «effect»: effect.sp <- effect ("sp", reg1, se=TRUE) with this output: sp AK BW NH OS RT SS 2.730101 2.885363 2.753774 2.750311

I can't seem to be able to change the font size in an effect display. I've tried the following: > par(cex.lab=4) > plot(effect ("alti",reg8), ylab="detection probability") and > plot(effect ("alti",reg8), ylab="detection probability", cex=4) but nothing changes. Can anyone help me? thanks. Emilie Berthiaume graduate student

Hello, I have come across a result that I cannot explain, and am hoping that someone else can provide an answer. A student fitted a mixed model using the lme function: out<- lme(fixed=Y~A+B+A:B, random=~1|Site). Y is a continuous variable while A and B are factors. The data set is balanced with the same number of observations in each combination of A and B. There are two hierarchical