library(perm)
typeIerrors <- 0
reps <- 1000
n1 <- 10
sd1 <- 5

n2 <- 30
sd2 <- 1

for (i in 1:reps){

  group1 <- rnorm(n=n1,sd=sd1)
  group2 <- rnorm(n=n2,sd=sd2)

  permRes <- permTS(group1,group2)$p.value
  if (permRes<.05){
    typeIerrors <- typeIerrors+1
  }
}
cat(sprintf('Type I error rate: %.2fn',typeIerrors/reps))