Statistical significance testing

1-sample z-test for a population proportion

Sample proportion

Sample size

Population proportion estimate

Desired significance level

Tails

1 tailed

2 tailed

Submit

Compare a sample proportion with a hypothesised population value. P-values can be calculated for one or two-tailed comparisons and are compared to a specified significance level.

Inputs are:

• a sample estimate of the proportion;
• sample size for the estimate;
• a population estimate for comparison;
• specified significance level; and
• whether test is one-tailed or two-tailed.

Outputs include:

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