What does a Z-score represent?

A Z-score represents the number of standard deviations a data point is from the mean of a distribution. Specifically, it has a mean of 0 and a standard deviation of 1, which is characteristic of a standard normal distribution. When you calculate a Z-score for a specific value, you transform it into a standardized score that allows for comparisons across different distributions. This standardization is particularly helpful in statistical analysis and interpretation, enabling you to see how far above or below average a particular score is in relation to the mean.

This concept of standardization is essential in various statistical applications, such as hypothesis testing and when determining probabilities in a normal distribution. Therefore, understanding that a Z-score has a mean of 0 and a standard deviation of 1 is fundamental to working with normally distributed data.