Representative sample

Definition

A representative sample is a subset of a population that accurately reflects the members of the entire population. It is used to make inferences about the population without surveying every individual.

5 Must Know Facts For Your Next Test

1. Representative samples reduce bias, ensuring that all subgroups of a population are included proportionally.
2. The accuracy of a representative sample depends on its size and how it is chosen (randomly or systematically).
3. Representative samples are essential for statistical inference, allowing conclusions about the population with known levels of confidence.
4. Stratified sampling can be used to ensure that different segments of the population are adequately represented in the sample.
5. Non-representative samples can lead to incorrect conclusions and undermine the validity of statistical analysis.

Review Questions

• Why is it important for a sample to be representative?
• What methods can be used to ensure a sample is representative?
• How does a non-representative sample affect statistical analysis?

Related terms

Population:

The entire group from which a sample is drawn for statistical analysis.

Sampling Bias:

A systematic error that occurs when some members of the population are less likely to be included in the sample than others.

Stratified Sampling:

A method of sampling that involves dividing the population into subgroups and selecting samples from each subgroup.