Hi John, This is not advanced enough for serious applications, but if you are just looking for a simple way to make example data, you could do something like:
gencor <- function(order, mu, sd, r) { X <- matrix(rnorm(prod(order), mean = mu, sd = sd), nrow = order[1], ncol = order[2]) R <- matrix(r, nrow = order[2], ncol = order[2]) diag(R) <- 1 X %*% chol(R) } cor(X <- gencor(c(100, 3), 10, 2, .5)) HTH, Josh On Fri, Mar 18, 2011 at 5:37 PM, John Sorkin <jsor...@grecc.umaryland.edu> wrote: > How would one generate data to be used in a simulation of a repeated measures > ANOVA given a known (1) within-person correlation with known (2) mean and SD > of data obtained at each of three times of observation? > Thanks, > John > John Sorkin > Chief Biostatistics and Informatics > Univ. of Maryland School of Medicine > Division of Gerontology and Geriatric Medicine > jsor...@grecc.umaryland.edu > Confidentiality Statement: > This email message, including any attachments, is for ...{{dropped:17}} ______________________________________________ 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.