The z-test for a single proportion

Abstract

The previous chapters looked at z-tests and t-tests for a single mean. However, social research is not always interested in investigating the mean of a distribution. We might be interested in other aspects of the population under investigation. For example, we might not be interested in the average height of people studying statistics, but rather the proportion of people above or below a certain height. Although this question is slightly different from one that investigates the mean of a distribution, the procedures for making an inference are basically the same. We will still conduct a z-test, but this time based on a sample proportion rather than a sample mean.