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What is z score?

Feb 27, 2024

What is z score?

Solution by Steps

step 1

To understand what a z-score is, we need to know that it is a statistical measurement that describes a value's relationship to the mean of a group of values

step 2

The z-score is calculated using the formula:

z = \frac{(X - \mu)}{\sigma}

where

X

is the value being measured,

\mu

is the mean of the data set, and

\sigma

is the standard deviation of the data set

step 3

A z-score tells us how many standard deviations away from the mean the value

X

is. If the z-score is 0, it means

X

is exactly at the mean. A positive z-score indicates

X

is above the mean, and a negative z-score indicates

X

is below the mean

Answer

The z-score is a measure of how many standard deviations a data point is from the mean.

Key Concept

Z-score

Explanation

A z-score quantifies the number of standard deviations a data point is from the mean of its data set.