// Otherwise, set the std to zero is enough.
	if len(resourceToFractions) == 2 {
		std = math.Abs((resourceToFractions[0] - resourceToFractions[1]) / 2)

	} else if len(resourceToFractions) > 2 {
		mean := totalFraction / float64(len(resourceToFractions))
		var sum float64
		for _, fraction := range resourceToFractions {
			sum = sum + (fraction-mean)*(fraction-mean)
		}