#!/usr/bin/ruby $:.unshift(File.dirname(__FILE__)+'/../lib/') # == Description # Polychoric Correlation using two-step and joint method # # Polychoric correlation in statsample requires installation of # the [statsample-bivariate-extension](https://rubygems.org/gems/statsample-bivariate-extension) # gem. This gem extends the Statsample::Bivariate class with useful # algorithms for polychoric and tetrachoric correlation. # # Statsample will automatically detect presence of polychoric/tetrachoric # algorithms so there is no need to explicitly require the gem. # # In this example we'll see how polychoric correlation can be # performed using statsample. require 'statsample' Statsample::Analysis.store(Statsample::Bivariate::Polychoric) do ct=Matrix[[rand(10)+50, rand(10)+50, rand(10)+1], [rand(20)+5, rand(50)+4, rand(10)+1], [rand(8)+1, rand(12)+1, rand(10)+1]] # Estimation of polychoric correlation using two-step (default) poly=polychoric(ct, :name=>"Polychoric with two-step", :debug=>false) summary poly # Estimation of polychoric correlation using joint method (slow) poly=polychoric(ct, :method=>:joint, :name=>"Polychoric with joint") summary poly # Uses polychoric series (not recomended) poly=polychoric(ct, :method=>:polychoric_series, :name=>"Polychoric with polychoric series") summary poly end if __FILE__==$0 Statsample::Analysis.run_batch end