have a look also at function rcor.test() from package ltm.

Best,
Dimitris

----
Dimitris Rizopoulos
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
    http://www.student.kuleuven.be/~m0390867/dimitris.htm


----- Original Message ----- From: "Monica Pisica" <[EMAIL PROTECTED]>
To: <r-help@r-project.org>
Sent: Thursday, May 08, 2008 9:05 PM
Subject: [R] applying cor.test to a (m, n) matrix



Hi everybody,

I would like to apply cor.test to a matrix with m rows and n columns and get the results in a list of matrices , one matrix for p.val, one for the statistic, one for the correlation and 2 for upper and lower confidence intervals, something analog with cor() applied to a matrix.

I have done my own function to get a matrix of p.values and i suppose i can build similar functions for all the others. But i have used for loops and i wonder if there is any way to actually use one of the functions from the "apply" family to do this in a quicker way.

Here is my little function:

cor.pval <- function(x, method = c("pearson", "kendal", "spearman"), digit=8) {
n <- dim(x)[2]
pval <- matrix(paste(rep("c", n*n), seq(1,n*n), sep = ""), n, n, byrow = T)
for (i in 1:n) {
for (j in 1:n){
pval[i, j] <- cor.test(x[,i], x[,j], method = method)$p.value
                                 }
                  }
pval <- matrix(round(as.numeric(pval),digit), n, n, byrow = T)
rownames(pval) <- colnames(x)
colnames(pval) <- colnames(x)
return(pval)
}

Thanks for any input,

Monica







_________________________________________________________________


esh_messenger_052008
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.



Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to