Variansi dari data 6, 8, 6, 7, 8, 7, 9, 7, 7, 6, 7, 8, 6, 5, 8, 7
adalah
1
Penyelesaian:
x̅ = Σxᵢ
n
= 6+8+6+7+8+7+9+7+7+6+7+8+6+5+8+7
= 112
16
= 7
Variansi (Ragam)
V = S² = 1 Σⁿ ( xᵢ - x̅)²
n i=1
= 1/16((6 - 7)² + (8 - 7)² + (6 - 7)² + (7 - 7)² + (8 - 7)² + (7 - 7)² + (9 - 7)² + (7 - 7)² + (7 - 7)² + (6 - 7)² + (7 - 7)² + (8 - 7)² + (6 - 7)² + (5 - 7)² + (8 - 7)² + (7 - 7)²
= 1/16((-1)² + (1)² + (-1)² + (0)² + (1)² + (0)² + (2)² + (0)² + (-1)² + (0)² + (1)² + (-1)² + (-2)² + (1)² + (0)²
= 1/16(1 + 1 + 1 + 0 + 1 + 0 + 4 + 0 + 1 + 0 + 1 + 1 + 4 + 1 + 0)
=1/16 × 16 = 1
Jadi, variansi data adalah 1