Hi Im attempting to build a sample variogram for 300 obersvations of longitudinal data. So what I need to do is compute the half squared differences between pairs of residuals (for instance if a subject has 4 obersvations, this is 4 choose 2 paird differences) for each subject. Also, then I need the corresponding time differences within each individual. So the end result will be a 300 by 2 matrix with columns corresponding to paired difference residuals within subject and time differences within subject. Basically im having trouble coding this kind of matrix in R, if anyone can help me out or give me some tips id appreciate it.
Thanks. Stuck in the for loop student ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html