我想随机化测试及其版本的顺序。 我的数据最后应该像这样:
> # subject Test t1 t2 t3 t4 > # 1 1 PFT A B C D > # 2 1 AWT B C D A > # 3 1 BWFT (...) > # 4 1 AUT > # 5 1 DPD-WN > # 6 1 DPT-NI > # 7 2 AWT > # (...) 250
我发现了一些对我有帮助的东西:
seed <- 42
blocksize <- 6
N <- 250 x 6
set.seed(seed)
subject = rep(1:ceiling(N/blocksize), each = blocksize)
a1 = data.frame(subject, rand=runif(length(subject)), envelope= 1:length(subject))
a2 = a1[order(a1$subject,a1$rand),]
a2$Test = rep(c("BWFT", "DPT-NI", "DPD-WN", "AUT", "PFT", "AWT"),times = length(subject)/6)
assign = a2[order(a2$envelope),]
head(assign,12)
您能帮我忙吗? 谢谢!
我越来越近:
(versions <- replicate(10, sample(c("A","B","C","D"), 4, replace=F)))
答案 0 :(得分:1)
您可以使用
生成所需值的矩阵tt <- t(replicate(nrow(a2), sample(LETTERS[1:4])))
colnames(tt) <- paste0("t", 1:4)
然后将其合并到您的数据框中
a2 <- cbind(a2, tt)
head(a2)
# subject rand envelope Test t1 t2 t3 t4
# 3 1 0.2861395 3 BWFT A B D C
# 6 1 0.5190959 6 DPT-NI C B A D
# 5 1 0.6417455 5 DPD-WN D B A C
# 4 1 0.8304476 4 AUT D C A B
# 1 1 0.9148060 1 PFT C A B D
# 2 1 0.9370754 2 AWT B D A C