# What is the variance of {-7, 42, -5, 1, 6, -3, 4, -2, 17, 53, -2, 4, 7, 88}?

##### 1 Answer

Population variance

Sample variance

#### Explanation:

**Method 1: Use a Spreadsheet**

Enter the data value in a column (or row)

and use the **VARP(range)** (for population variance) or the **VAR(range)** (for sample variance) function.

**Method 2: Manual Calculation**

Find the sum of the data values.

Find the mean value (by dividing the sum by the number of data values)

For each data value calculate the difference between it and the mean.

For each data value calculate the square of the difference between it and the mean.

Calculate the sum of the squares

For population variance, divide the sum of the squares by the number of data value; for sample variance, divide the sum of the squares by (1 less than the number of data values).

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Use **Population Variance** if the data represents all entities in the universe of discourse.

Use **Sample Variance** if the data represents a random selection of entities from the universe of discourse.