Ruby Statistics

A basic ruby gem that implements some statistical methods, functions and concepts to be used in any ruby environment without depending on any mathematical software like R, Matlab, Octave or similar.

Unit test runs under the following ruby versions:

  • Ruby 2.5.1.
  • Ruby 2.6.0.
  • Ruby 2.6.3.
  • Ruby 2.6.5.
  • Ruby 2.7.

We got the inspiration from the folks at JStat and some interesting lectures about Keystroke dynamics.

Some logic and algorithms are extractions or adaptations from other authors, which are referenced in the comments. This software is released under the MIT License.


Add this line to your application's Gemfile:

gem 'ruby-statistics'

And then execute:

$ bundle

Or install it yourself as:

$ gem install ruby-statistics

Basic Usage

just require the statistics gem in order to load it. If you don't have defined the Distribution namespace, the gem will assign an alias, reducing the number of namespaces needed to use a class.

Right now you can load:

  • The whole statistics gem. require 'statistics'
  • A namespace. require 'statistics/distribution'
  • A class. require 'statistics/distribution/normal'

Feel free to use the one that is more convenient to you.

Hello-World Example

require 'statistics'

poisson = # Using Distribution alias.
normal = # Using all namespaces.


You can find a bit more detailed documentation of all available distributions, tests and functions in the Documentation Index


After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to


Bug reports and pull requests are welcome on GitHub at This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.


The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the Statistics project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.


You can contact me via: