Z-test excel

In statistics, a z-score tells us how many standard deviations away a value is from the mean. We use the following formula to calculate a z-score:

z = (X – μ) / σ

where:

• X is a single raw data value
• μ is the mean of the dataset
• σ is the standard deviation of the dataset

This tutorial explains how you can calculate z-scores for raw data values in Excel.

How to Calculate Z-Scores in Excel

Suppose we have the following dataset and we would like to find the z-score for every raw data value:

We can perform the following steps to do so.

Step 1: Find the mean and standard deviation of the dataset.

First, we need to find the mean and the standard deviation of the dataset.

The following formulas show how to do so:

The mean turns out to be 14.375 and the standard deviation turns out to be 4.998.

Step 2: Find the z-score for the first raw data value.

Next, we’ll find the z-score for the first raw data value using the formula z = (X – μ) / σ.

Cell C2 shows the formula we used to calculate the z-value in cell B2.

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