Summarise categorical or continuous data

2-sample z-test to compare sample proportion

	Sample 1	Sample 2
Sample proportion
Sample size

Desired significance level

1 tailed

2 tailed

Submit

Compare two sample proportions using the 2-sample z-test. P-values can be calculated for one or two-tailed comparisons and are compared results to a specified significance level.

Inputs are:

• sample proportions for each sample;
• sample sizes for each sample;
• specified significance level; and
• whether test is one-tailed or two-tailed.

Outputs include:

• difference in sample proportions;
• Asymptotic (normal approximation) confidence limits (based on specified significance level) for the proportions and their difference;
• z and P values for the difference in proportions and their interpretation;
• whether or not z * p values are > 5 (to ensure test validity); and
• a plot of the confidence limits.