# HW 3 skew.R JLCY, 19 Dec 2013

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skew = function(x) {
    n <- length(x)
    nfact <- n/((n - 1) * (n - 2))
    xm <- mean(x)
    xv <- sqrt(var(x))
    skw <- sum((x - xm)^3)
    skew <- (nfact * skw)/xv^3
    skew
}