Estimates variance based on a sample. In addition to numbers, text and logical values such as TRUE and FALSE are included in the calculation.
Syntax
VARA(value1,value2,...)
Value1, value2, ... are 1 to 30 value arguments corresponding to a sample of a population.
Remarks
- VARA assumes that its arguments are a sample of the population. If your data represents the entire population, you must compute the variance using VARPA.
- Arguments that contain TRUE evaluate as 1; arguments that contain text or FALSE evaluate as 0 (zero). If the calculation must not include text or logical values, use the VAR worksheet function instead.
- VARA uses the following formula:
where x is the sample mean AVERAGE(value1,value2,…) and n is the sample size.
Example
Suppose 10 tools stamped from the same machine during a production run are collected as a random sample and measured for breaking strength.
The example may be easier to understand if you copy it to a blank worksheet.
How?- Create a blank workbook or worksheet.
- Select the example in the Help topic. Do not select the row or column headers.
Selecting an example from Help
- Press CTRL+C.
- In the worksheet, select cell A1, and press CTRL+V.
- To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Tools menu, point to Formula Auditing, and then click Formula Auditing Mode.
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