Adjusting p values of a matrix
Dear all, I have an n x n matrix of p-values. The matrix is symmetrical, as it describes the "each against each" p values of correlation coefficients. How can I best correct the p values of the matrix? Notably, the total number of the tests performed is n(n-1)/2, since I do not test the correlation of each variable with itself. That means, I only want to correct one half of the matrix, not including the diagonal. Therefore, simply writing pmat <- p.adjust( pmat, method= "fdr" ) # where pmat is an n x n matrix ...doesn't cut it. Of course, I can turn the matrix in to a three column data frame with n(n-1)/2 rows, but that is slow and not elegant. regards, j.
-------- Dr. January Weiner 3 -------------------------------------- Max Planck Institute for Infection Biology Charit?platz 1 D-10117 Berlin, Germany Web?? : www.mpiib-berlin.mpg.de Tel? ?? : +49-30-28460514