Provides advanced bivariate statistics:

• Tetrachoric correlation
• Polychoric correlation

• Statsample::Bivariate::Polychoric class provides polychoric correlation
• Statsample::Bivariate::Tetrachoric class provides tetrachoric correlation

require 'statsample' a=40 b=10 c=20 d=30 tetra=Statsample::Bivariate::Tetrachoric.new(a,b,c,d) puts tetra.summary 

require 'statsample' ct=Matrix[[58,52,1],[26,58,3],[8,12,9]] poly=Statsample::Bivariate::Polychoric.new(ct) puts poly.summary 

• Statsample

This gem is a statsample dependency. If you want to install it separatly

• gem install statsample-bivariate-extension

BSD 2-Clause (see LICENSE.txt)