Statistics - Data Collection Terms

Key terms and defintions for data collection in statistics.

Population

The whole set of items that are of interest.

Census

Observes or measures every member of a population.

Sample

A selection of observations taken from the population.

Sampling Unit

An individual unit of a population.

Sampling Frame

A list of sampling units.

Simple Random Sampling

Every sampling unit has an equal chance of being selected.

Systematic Sampling

Each sampling unit are chosen at regular intervals in an ordered list.

Stratified Sampling

Population divided into mutually exclusive strata and simple random sampling carried out in each strata.

Quota Sampling

An interviewer or researcher selects a sample that reflects the characteristics of the whole population.

Opportunity Sampling

Sample taken from people who are available at time of study who meet the criteria.