*38*

A

**two proportion z-test**is used to test for a difference between two population proportions. The test statistic is calculated as:**z**= (p

_{1}-p

_{2}) / √(p(1-p)(1/n

_{1}+1/n

_{2})

where:

- p = total pooled proportion
- p
_{1}= sample 1 proportion - p
_{2}= sample 2 proportion - n
_{1}= sample 1 size - n
_{2}= sample 2 size

To perform a two proportion z-test, simply fill in the information below and then click the “Calculate” button.

z-statistic: 0.31917

p-value (one-tailed): 0.37480

p-value (two-tailed): 0.74960