Sample Standard Deviation

mctad.sampleStandardDeviation() accepts an Array of Numbers assumed to be a sample and returns their standard deviation as a Number. It is simply the square root of mctad.sampleVariance(). More at the Wikipedia article.

mctad.sampleStandardDeviation = function (data) { if (!Array.isArray(data) || data.length === 0 ) { return null; } return Math.sqrt(this.sampleVariance(data)); };