Sxx Variance Formula !exclusive! ✰

The Sample Variance ( s2s squared ) formula is used to measure how much a set of numbers spreads out from their average.

Suppose we have a dataset of exam scores: Sxx Variance Formula

9. Programming Sxx (Python and R)

In Python (NumPy):

import numpy as np
x = np.array([2, 4, 6, 8, 10])
Sxx = np.sum((x - np.mean(x))**2)
# Or: Sxx = np.sum(x**2) - (np.sum(x)**2)/len(x)
print(Sxx)  # 40.0

• (2-6)² = 16
• (4-6)² = 4
• (6-6)² = 0
• (8-6)² = 4
• (10-6)² = 16

So Sxx is just the numerator of the variance (before dividing by ( n-1 )). The Sample Variance ( s2s squared ) formula