x <- c(10, 9, 5, 6, 7, 4, 3, 5, 6, 8)

y <- c(1,2,1,2,2,1,3,3,1,2)

"pPareto" <- function(x, alpha, x0)
{
  result <- 1 - (x0/(x+x0))^alpha
  return(result)
}

install.packages("truncgof")

library(MASS)
library(truncgof)

set.seed(123)

treshold <- y

xc  <- x     # complete sample

xt <- xc[xc >= y]     # left truncated sample

ks.test(xt, "pPareto", list(alpha = 2, x0 = location), H = y)