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STDEV
Estimates standard deviation based on a sample. The standard deviation is a measure of how widely values are dispersed from the average value (the mean).
Syntax
STDEV(number1,number2,...)
Number1,number2,... are 1 to 30 number arguments corresponding to a sample of a population. You can also use a single array or a reference to an array instead of arguments separated by commas.
Remarks
- Logical values such as TRUE and FALSE and text are ignored. If logical values and text must not be ignored, use the STDEVA spreadsheet function.
- STDEV assumes that its arguments are a sample of the population. If your data represents the entire population, then compute the standard deviation using STDEVP.
- The standard deviation is calculated using the "nonbiased" or "n-1" method.
- STDEV uses the following formula:
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 spreadsheet.
How?
- Create a blank spreadsheet.
- Select the example in the Help topic.
Selecting an example from Help
- Press CTRL+C.
- In the spreadsheet, select cell A1, and press CTRL+V.
- To switch between viewing the formula that returns the result and the result in the cell, select the cell and press F2 and then ENTER, or click Commands and Options on the spreadsheet toolbar, click the Formula tab, and look in the Formula in active cell (active cell) box.
| Strength | |
|---|---|
| 1345 | |
| 1301 | |
| 1368 | |
| 1322 | |
| 1310 | |
| 1370 | |
| 1318 | |
| 1350 | |
| 1303 | |
| 1299 | |
| Formula | Description (Result) |
| =STDEV(A2:A11) | Standard deviation of breaking strength (27.46391572) |