Skip to content


Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time


npm version

SeGLiR is a javascript library for rapid A/B-testing with Sequential Generalized Likelihood Ratio Tests.

Sequential GLR tests are a family of sequential hypothesis tests, i.e. tests that stop as soon as a significant result has been detected. Compared to classical fixed samplesize tests, sequential GLR tests may give a significant decrease in the needed samplesize, while keeping the same type-1 and type-2 error guarantees. Below is a comparison of the expected samplesize for fixed samplesize and sequential GLR tests at the same levels. For a more detailed explanation of this family of tests (as well as the graph below), see the reference.

Expected samplesize comparison

Try out this demo to compare samplesize from the fixed samplesize test versus the sequential GLR test yourself.

SeGLiR currently contain these tests:

  • comparing two bernoulli proportions (for instance for comparing conversion on a website)
  • comparing two normal means (with equal, known or unknown variance)
  • choosing the best arm in a multi-armed bandit setting (with δ-PAC guarantees)

Improvements and additions are welcome, take a look at issues for suggested improvements.


The recommended way is to install SeGLiR via node package manager (install node.js if you don't already have it):

npm install seglir


If you're not running SeGLiR in node, note that SeGLiR requires jStat.js available.

var glr = require("seglir");
// create an instance of a two-sided test comparing bernoulli proportions, with indifference region with size 0.01, alpha-level = 0.05, beta-level = 0.10
var test = new glr.test("bernoulli", "two-sided", 0.01, 0.05, 0.10);
// add data as it comes in
test.addData({x : 0});
test.addData({x : 0, y : 0});
test.addData({y : 1});
// when addData() returns string 'true' or 'false', the test is concluded
// 'true' means the null hypothesis was accepted
// 'false' means the null hypothesis was rejected (and the alternative hypothesis accepted)

// get bias-adjusted estimates

For a complete function reference, see the reference.

Building from source

Make sure you have grunt and node installed. To install the development dependencies run npm install and to build it run grunt in the root directory.


SeGLiR is distributed under the MIT License.


Javascript library for rapid A/B-testing with Sequential Generalized Likelihood Ratio tests







No releases published


No packages published