7th Grade · Statistics & Probability
Sample Statistic
7.SP.A.2
Definition
A numerical value calculated from sample data, used to estimate the corresponding population parameter. Common statistics: x̄ (sample mean) and p̂ (sample proportion). Changes from sample to sample.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
Examples
- Sample of 30 students: sample mean x̄ = 1,920 ÷ 30 = 64 inches.
- Use x̄ to estimate μ, and p̂ to estimate p.
Key rule
A sample statistic is what we calculate; a population parameter is what we estimate.
Memory hook
Calculated from the sample, used to guess the population.