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Two-sample test for independent proportions - using R

Two-sample test for independent proportions


The application prop.test in R outputs the chi square statistic as the test statistic along with the confidence interval for the difference. The data should be provided as a matrix with 2 columns giving the counts of successes and failures, respectively.

Gives something like this:

2-sample test for equality of proportions with continuity correction

data:  tab1
X-squared = 2.7412, df = 1, p-value = 0.09779
alternative hypothesis: two.sided
95 percent confidence interval:
 -0.50722061  0.02722061
sample estimates:
prop 1 prop 2
  0.12   0.36