computeLorenzCurve <- function(x, plot = T) {
    nobs <- length(x)
    sortedx <- sort(x)
    abscissa <- (1:nobs)/nobs
    ordinate <- cumsum(sort(x))/sum(x)
    
    if (plot) {
        plot(ordinate, abscissa, main = "Lorenzkurve")
        abline(a = 0, b = 1)
    }
    
    return(cbind(abscissa, ordinate))
}