Merge pull request #11 from onli/chisquare_example

Add an example for chi-square homogeneity test

Author: v0dro

examples/chisquare_test.rb

@@ -0,0 +1,23 @@
+#!/usr/bin/ruby
+$:.unshift(File.dirname(__FILE__)+'/../lib')
+require 'statsample'
+
+Statsample::Analysis.store(Statsample::Test::ChiSquare) do
+  # Collect the two vectors with the categorical data (raw number of occurences) into one matrix. Here
+  #--------------------------------------------
+  #| category | observation 1 | observation 2 |
+  #|------------------------------------------|
+  #|    A     |      100      |      20       |
+  #|    B     |      50       |      70       |
+  #|    C     |      30       |      100      |
+  #|------------------------------------------|
+  #
+  m=Matrix[[100, 50, 30],[20, 70, 100]]
+  x_2=Statsample::Test.chi_square(m)
+  # after the test is done, look at the p-value.
+  puts x_2.probability
+end
+
+if __FILE__==$0
+  Statsample::Analysis.run_batch
+end