| Student | Score | Deviation from mean | | --- | --- | --- | | 1 | 80 | 0 | | 2 | 70 | -10 | | 3 | 90 | 10 | | 4 | 85 | 5 | | 5 | 75 | -5 |
s² = Sxx / (n-1)
| Student | Score | Deviation from mean | Squared deviation | | --- | --- | --- | --- | | 1 | 80 | 0 | 0 | | 2 | 70 | -10 | 100 | | 3 | 90 | 10 | 100 | | 4 | 85 | 5 | 25 | | 5 | 75 | -5 | 25 | Sxx Variance Formula
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: | Student | Score | Deviation from mean
s² = Sxx / (n-1) = 250 / (5-1) = 62.5
Sxx = Σ(xi - x̄)²
The Sxx variance formula is a part of this calculation: Sxx Variance Formula