search for: att0

...9;s using a permutation method to calculate p value. But I would like to know exactly how the permutation works. #calculates null statistics tt0 <- 0 set.seed(123) B <- 100 for(i in 1:B) { v <- sample(y) tt0 <- c(tt0,ttest(dat,v)$tt) } tt0 <- tt0[-1] #form p-values att <- abs(tt) att0 <- abs(tt0) v <- c(rep(T,m),rep(F,m*B)) v <- v[rev(order(c(att,att0)))] u <- 1:length(v) w <- 1:m p <- (u[v==TRUE]-w)/(B*m) p <- p[rank(-att)] For some reason, I couldn't get any results for p. Maybe R encoded T and F to corresponding numerical ones. Any idea? Thanks, Ho...