平方和计算器公式

How to Calculate the Sum of Squares

Formula

SS = Sum of (xi - mean)^2

For each value, subtract the mean, square the result, and add them up. The sum of squares quantifies total variability in the data and is the numerator in variance calculations.

  • Population Variance = SS / n
  • Sample Variance = SS / (n - 1)
  • 计算示例

    Find the sum of squares for 3, 5, 7, 9.

    1. Mean = (3 + 5 + 7 + 9) / 4 = 24 / 4 = 6
    2. Deviations: 3-6=-3, 5-6=-1, 7-6=1, 9-6=3
    3. Squared deviations: 9, 1, 1, 9
    4. SS = 9 + 1 + 1 + 9 = 20