var StdDeviation = require("monoid-std-deviation");

var list = [
    new StdDeviation(52),
    new StdDeviation(72),
    new StdDeviation(42),
    new StdDeviation(63),
    new StdDeviation(65),
    new StdDeviation(93)
];

var result = list.reduce(function(a, b) { return a.concat(b); });

console.log(result.value());
//prints 15.98697386415995