Mathematics - Statistics - Measures of Spread - Standard deviation and variance - Variance and Standard Deviation

10 steps using dataset {4, 8, 6, 5, 3}: (1) Find mean: (4+8+6+5+3)/5 = 26/5 = 5.2. (2) Find each deviation from mean: -1.2, 2.8, 0.8, -0.2, -2.2. (3) Notice: sum of deviations = 0 (always!). That's why we can't just add them. (4) Square each deviation: 1.44, 7.84, 0.64, 0.04, 4.84. (5) Sum of square