What is a Z-Score?

A Z-score, also known as a standard score, is a statistical measurement that describes a value’s relationship to the mean of a group of values. It is measured in terms of standard deviations from the mean. If a Z-score is 0, it indicates that the data point’s score is identical to the mean score.

The Z-Score Formula

z = (x - μ) / σ

Where:

• x is the raw score
• μ is the population mean
• σ is the population standard deviation