Variance (σ²) = E[(xi - μ)²]
To derive the Sxx variance formula, let's start with the definition of variance:
where E denotes the expected value, and μ represents the population mean. Sxx Variance Formula
s² = Sxx / (n-1) = 250 / (5-1) = 62.5
| Student | Score | Deviation from mean | | --- | --- | --- | | 1 | 80 | 0 | | 2 | 70 | -10 | | 3 | 90 | 10 | | 4 | 85 | 5 | | 5 | 75 | -5 | Variance (σ²) = E[(xi - μ)²] To derive
Let's consider an example to illustrate the calculation of Sxx:
Sxx = 0 + 100 + 100 + 25 + 25 = 250
Q: What is the relationship between Sxx and variance? A: Sxx is used to calculate variance by dividing Sxx by (n-1), where n is the sample size.