A ranking algorithm implementation to Ruby on Rails applications that use Active Record.
Sigma is an open source implementation of true skill algorithm's concept to Ruby on Rails applications that use Active Record.
Sigma is released under the MIT license: www.opensource.org/licenses/MIT
Well, this is Sigma I really hope you enjoy and use it a lot, I'm still working on it so dont be shy, let me know if something get wrong opening a issue, then I can fix it and we help each other ;)