StatisticsCalc

Statistics gem to help with a few basic statistical calculations such as the lower bound of a Wilson score confidence interval for a Bernoulli distribution.

Installation

Add this line to your application's Gemfile:

gem 'statistics_calc'

And then execute:

$ bundle

Or install it yourself as:

$ gem install statistics_calc

Usage

Additional paramaters are available for some functions

CI Lower Bound of the Wilson core confidence interval for a Bernoulli distribution

http://www.evanmiller.org/how-not-to-sort-by-average-rating.html

StatisticsCalc.two_point_ranking(first_count: 350, second_count: 15) == 0.9335708863805254

Hot Rating

https://bibwild.wordpress.com/2012/05/08/reddit-story-ranking-algorithm

# if Time.now = 2016-12-16 12:36:43 -0600 then
StatisticsCalc.hot(upper_value: 350, lower_value: 15) == 551.3738607329627

Performance Rating

StatisticsCalc.performance(upper_value: 350, lower_value: 15) == 2.5250448070368448

Percent Delta

StatisticsCalc.percent_delta(current_value: 350, old_value: 15) == 22

Development

After checking out the repo, run bin/setup to install dependencies. 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 rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/statistics_calc.

License

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

nanosplit / statistics_calc