If a constant of 5 is subtracted from all of the scores, the standard deviation _________.
A) decreases by 5
B) decreases by
C) remains the same
D) decreases by 5/ N

Question

If a constant of 5 is subtracted from all of the scores, the standard deviation _________.
A) decreases by 5 
B) decreases by 
C) remains the same 
D) decreases by 5/ N

Quizplus · Accepted Answer

The standard deviation is a measure of dispersion from the mean. Subtracting a constant from all scores does not affect the relative distances between the scores, and therefore does not affect the measure of dispersion, which is the standard deviation. Thus, the standard deviation would remain the same.

If a Constant of 5 Is Subtracted from All of the Scores