How to Find Sample Variance on a TI-84 Calculator


The sample variance tells us how spread out the values are in a given .

Typically denoted as s2, it is calculated as:

s2 = Σ (xix)2 / (n-1)

where:

  • x: sample mean
  • xi: the ith value in the sample
  • n: the sample size

The following step-by-step example shows how to calculate the sample variance for the following sample:

Sample: 2, 4, 4, 7, 8, 12, 14, 15, 19, 22

Step 1: Enter the Data

First, we will enter the data values.

Press Stat, then press EDIT. Then enter the values of the sample in column L1:

Step 2: Find the Sample Variance

Next, press Stat and then scroll over to the right and press CALC.

Then press 1-Var Stats.

In the new screen that appears, press Enter.

The sample standard deviation is Sx = 6.783149056.

To find the sample variance, we need to square this value. To do so, press VARS and then press 5:

In the new window that appears, press 3 to select the sample standard deviation:

Lastly, press the x2 button to square the sample standard deviation:

sample variance on TI-84 calculator

The sample variance turns out to be 46.0111.

x