ABSTRACT
The z-score is a helpful tool to quickly understand how far a particular score is from the mean of the sample. Every raw score in a distribution has a corresponding z-score. The z-score for the mean of a distribution is set at 0. If a particular score is larger than the mean, then the z-score will be positive, and if the particular score is smaller than the mean, then the z-score will be negative. As raw scores get farther from the mean, the absolute value of their z-scores gets larger. So a z-score of 2 is farther from the mean than a z-score of 1. Similarly, a z-score of -2 is farther from the mean than a z-score of -1. Finally, z-scores tend to range from -3 to +3, as most scores will fall within three standard deviations of the mean. The excerpt presents data on anthropometry, or physical measures of the human body.
