#Example 3.1 Hamilton Depression Scale Factor IV

sf.data <- read.table("https://edoras.sdsu.edu/~babailey/stat672/t3-1.txt", header=T)
sf.data
attach(sf.data)

wilcox.test(y, x, paired=TRUE, alternative="less")

#or the exact test:
library(exactRankTests)
wilcox.exact(y, x, paired = TRUE, alternative = "less")

#There is a R psignrank function