错误:在每列的R中循环？

Question

我有一些数据并试图做分析。我不知道如何使用R，但我看了很少的视频在互联网上，并试图模仿相同的测试，我需要。我想做的是尝试比较前四行(1-4行)和接下来的四行(4-8行)。在得到结果后，我想将相同的测试应用于下一列，因此我将有4个不同的p值。请找到一个示例图像附加附像。我总共有4列，这是先导测试，以后将用大的列大小执行。请问是否有人能告诉我做错了什么，并编辑代码。我很乐意为大家提供帮助。

Test = matrix(c(120, 115, 132, 117, 116,117,125,120,110,113,128,115),ncol=4, nrow = 4)
Test=t(Test)

Drug = matrix(c(88, 80, 85, 85, 83,84,90,83,83,79,86,82),ncol=4, nrow = 4)
Drug=t(Drug)
mydata<-cbind(Test,Drug)


for (i in 1:4)
wilcox.test(mydata[i,1:4],mydata[i,5:8], mu=0, alt="two.sided", paired=T,  conf.int=F,conf.level = 0.99, exact=T,correct=T)

Answer 1

为此，我建议使用data.frame或data.table，列指定组(对应于示例中的行，例如A、B、C)，一列指定测试/药物，一列指定值：

library(data.table)
Test <- c(120, 115, 132, 117, 116,117,125,120,110,113,128,115)
Drug <- c(88, 80, 85, 85, 83,84,90,83,83,79,86,82)
groups <- rep(c(rep("A", 4), rep("B", 4), rep("C", 4)), 2)
variable <- c(rep("test", length(Test)), rep("drug", length(Drug)))
dt <- data.table(group = groups, variable = variable, value = c(Test, Drug))

# >dt
#     group variable value
#  1:     A     test   120
#  2:     A     test   115
#  3:     A     test   132
#  4:     A     test   117
#  5:     B     test   116
#  6:     B     test   117
#  7:     B     test   125
#  8:     B     test   120
#  9:     C     test   110
# 10:     C     test   113
# 11:     C     test   128
# 12:     C     test   115
# 13:     A     drug    88
# 14:     A     drug    80
# 15:     A     drug    85
# 16:     A     drug    85
# 17:     B     drug    83
# 18:     B     drug    84
# 19:     B     drug    90
# 20:     B     drug    83
# 21:     C     drug    83
# 22:     C     drug    79
# 23:     C     drug    86
# 24:     C     drug    82
#     group variable value

每组测试值与药物值之间的关系是：

dt_stat <- dt[, .(p_value = wilcox.test(value~variable, mu=0, alt="two.sided", paired = TRUE,
  conf.int = FALSE, conf.level = 0.99,exact = TRUE, correct = TRUE)$p.value),
  by = .(group)]

# > dt_stat
#    group    p_value
# 1:     A 0.09751254
# 2:     B 0.09751254
# 3:     C 0.12500000