The Excel VARA function estimates the variance of a sample of data. Unlike the VAR function, the VARA function evaluates text values and logicals in references.
Syntax:= VARA (number1, [number2], …)
The VARA function syntax has the following arguments:
- Number1 (required argument) – This is the first argument corresponding to a population.
- Number 2,.. (optional argument) – Here, the number arguments can be up to 254 values or arrays of values that provide at least two values to the function. However, we can only enter up to 30 number arguments in Excel 2003 and earlier versions.
Example: Let’s look at some Excel VARA function examples and explore how to use the VARA function as a worksheet function in Microsoft Excel:
Suppose we are given data about the height of children from three cities, as shown below:
For variance, the formula used is:
In the example above, we took the arguments for the VARA function as input in the form of three cell ranges. However, we can also enter the figures directly, either as individual numbers or number arrays.
For example, if you wanted to include two further heights, of 163cm and 155cm into the sample, you could add these directly into the above function as follows:
or, as an array of numbers:
- VARA assumes that its arguments are a sample of the population. If your data represents the entire population, you must compute the variance by using VARPA.
- Arguments can be the following: numbers; names, arrays, or references that contain numbers; text representations of numbers; or logical values, such as TRUE and FALSE, in a reference.
- Logical values and text representations of numbers that you type directly into the list of arguments are counted.
- Arguments that contain TRUE evaluate as 1; arguments that contain text or FALSE evaluate as 0 (zero).
- If an argument is an array or reference, only values in that array or reference are used. Empty cells and text values in the array or reference are ignored.
- Arguments that are error values or text that cannot be translated into numbers cause errors.
- If you do not want to include logical values and text representations of numbers in a reference as part of the calculation, use the VAR function.
- VARA uses the following formula:
where x is the sample mean AVERAGE(value1,value2,…) and n is the sample size.