What does a z-score indicate?

A z-score indicates how many standard deviations a particular score is away from the mean of a dataset. It provides a way to understand the relative position of an individual score within the overall distribution. For example, a z-score of 1 means the score is one standard deviation above the mean, while a z-score of -2 denotes a score two standard deviations below the mean. This standardization allows for easy comparison between scores from different datasets or distributions.

In contrast, the average score of a dataset simply represents the central value and does not provide information about individual scores relative to that average. The proportion of scores above the median is a different statistical measure that does not relate to the standard deviation context, and the highest score within a dataset represents an absolute value rather than a standardized comparison. Thus, the z-score uniquely captures the distance from the mean in terms of standard deviations, making this concept particularly valuable in statistics.