NormalDistribution

https://github.com/RichieAHB/normal-distribution

A small javascript module for working with normal distributions.

The class can be instantiated like so:

const normDist = new NormalDistribution(mean, standardDeviation);

With no arguments the distribution will be a standard normal distribution with mean = 0 and standardDeviation = 1.

The four main methods that can be called are:

#pdf(value)

Accepts an integer argument and returns the probability denisty at that point in the distribution; useful for drawing the curve.

#cdf(value)

Accepts an integer argument and returns the probability of a random variable being below the one argument passed to the method.

#probabilityBetween(value1, value2)

Accepts two integer arguments and returns the probability of a random variable being between the two arguments passed.

#zScore(value)

Accepts an integer argument and returns the z-score for that value.

Note: the z-table used in this module gives probabilities for up to 3.5 standard deviations from the mean