For a sample of data, we use the sample mean (x̄) as an estimate of the population mean (μ). The sample variance (s²) is calculated as:
Sxx = 0 + 100 + 100 + 25 + 25 = 250
Suppose we have a dataset of exam scores: Sxx Variance Formula
| Student | Score | | --- | --- | | 1 | 80 | | 2 | 70 | | 3 | 90 | | 4 | 85 | | 5 | 75 | For a sample of data, we use the
s² = (1/(n-1)) * Σ(xi - x̄)²