Question

the sum of squares of the deviation of the values of a variable is least when the deviations are measured from​

Answer 1

Answer:

Mean deviation is the arithmetic average of the deviations of the observed values from an average of the observed values.

Mean deviation from the mean calculates the arithmetic average of the deviations of the observed values from mean of the observed values. Sum of the squares of the deviations is minimum when deviations are taken from mean as mean is the arithmetic average of the series and disperse the whole series into individual minimum value therefore the sum of their squares is minimum.