Elo rating system in javascript, revealing module pattern.

elo.js

var elo = (function(){

  var k = 32;

	function setKFactor(n){
		k = n;
	};

	function getExpected(ratingA, ratingB){
		return 1/ (1+Math.pow(10, ((ratingB-ratingA)/400)));
	};

	function updateRating(expected,actual,current){
		return parseInt(current+k*(actual-expected),10);
	}

	return {
		setKFactor:setKFactor,
		getExpected:getExpected,
		updateRating:updateRating
	};
}());