simple-statistics is a Javascript library I wrote to understand statistics better. It’s useful as a node module as well as in the browser with visualization frameworks like d3.

Here are some of the kinds of things you can do:

// Find the mean (average) of a set of numbers. This // takes an array of numbers var mean = ss . mean ([ 1 , 2 , 3 ]); // The variance of numbers is the sum of the squared // differences between numbers and the mean of the list. var variance = ss . variance ([ 1 , 2 , 3 ]); // Create a linear regression based on a dataset of // two-dimensional arrays. This returns a new function // that you can call for the value of the line at // each X value. var linear_regression_line = ss . linear_regression () . data ([[ 0 , 1 ], [ 2 , 2 ], [ 3 , 3 ]]). line (); linear_regression_line ( 5 ); // The r-squared function can be given a dataset just // like linear regressions, and it'll tell you roughly how // close the linear regression comes to actually estimating // the data. var r_squared = ss . r_squared ([[ 1 , 2 ]], linear_regression_line );

As you can see, it does a bit of descriptive statistics as well as statistical inference, and there’s even some code for a bayesian classifier in there.

Libraries like science.js, R, and descriptive-statistics are written by smarter people and are probably more performant and shiny. The point of simple-statistics is that it’s simple, accessible, and aims to be as low on concept as possible.