ABSTRACT
Statistical Guide: A standard score (also known as a z-score) tells us how many standard deviation units a person is from the mean of some reference group. For example, a person who has a standard score of 1.5 is one and one-half standard deviations above the mean of a group with which he or she is being compared. A person who has a standard score of -2.0 is two standard deviations below the mean of the group.
