stratification

Stratification is the dividing of a population into groups with shared charateristics. Each group is called a strata.

For wages you could create your strata by grouping together the population by payment frequency. Eg group together everyone who is paid weekly, fortnightly and monthly.

Another way to stratify the population could be by salary range. eg group together everyone who is paid an annual salary of $0 – 50k, $51 – $100k, $101 – $150k etc.

The purpose of stratification is to ensure that an audit sample selected is representative of the population as a whole.

if an auditor were to randomly select a sample from a population of wages, the sample may not include anyone from the $101 – $150 group, because that group may be very small, the $0 – 50k group may be very large, so possibly the random sample may only include people from this group, this would not be representative of the entire population.

By stratifiying the population into groups (strata) the auditor can select a random sample from each group, this will give a much better representative sample.

Stratification is a way of decreasing sampling risk without increasing sample size (thanks ejee 🙂

Thanks 🙂

thanks dear