Standard Deviation

Definition

Standard deviation is a measure used to quantify the amount of variation or dispersion in a set of values. It tells us how much on average scores deviate from their mean value.

Related terms

Mean:

The average value of a set of numbers.

Normal Distribution:

A probability function that describes how the values of a variable are distributed. It is symmetric and bell-shaped.

Z-Score: A statistical measurement that describes a value's relationship to the mean of a group of values.