7th Grade · Statistics & Probability
Representative
7.SP.A.1
Definition
A sample in which the proportions of key subgroups match those of the population. Results from a representative sample can be used to make valid inferences about the population.
Examples
- A population that is 40% Hispanic, 30% White, 20% Black, 10% Asian, sampled proportionally.
- Surveying only honors classes (70% White, 20% Asian) is NOT representative.
Key rule
A non-representative sample produces biased results.
Memory hook
The sample mirrors the population's makeup.