Sxx Variance Formula -

Or equivalently:

Sxx = Σ x_i^2 − n * x̄^2

There are two primary ways to express the sample variance formula. 1. The Definitional Formula Sxx Variance Formula

Raw sum of squares ( \sum x_i^2 ) is not Sxx. Never use raw sum for variance or regression without subtracting the correction term. Or equivalently: Sxx = Σ x_i^2 − n