Question

55. The elimination of extreme scores at the top of the set has the effect of:
(A) Lowering the mean
(B) Raising the mean
(C) No effect
(D) Difficult to tell​

Answer 1

$\bold \red{Raising \: the \: mean}$

Answer 2

(B) Raising the mean

The mean is an arithmetic average of the data set, determined by dividing the total of all data points by the number of data points in the data set. Thus, considering the data to be arranged in a ascending order and the extreme scores at the top are of the lowest values in the dataset, this has an effect of raising the mean as all lower value terms are eliminated.

The formula of mean = sum of terms / number of terms

Thus, if lower level of values are reduced, the number of terms are reduced too. Thus, resulting in higher mean value.