@STDEV

Calculates the standard deviation of the specified data set (expList). The calculation is based upon a sample of a population. Standard deviation is a measure of how widely values are dispersed from their mean (average).

This function assumes that expList represents a sample of a population. If you want expList to represent the entire population, use @STDEVP. For large samples, the functions return similar values.

@STDEV is calculated using the "nonbiased" or "n-1" method.

@STDEV uses the following formula:

formula for @STDEV

Syntax

@STDEV (SKIPNONE | SKIPMISSING | SKIPZERO | SKIPBOTH, expList)
Parameter Description

SKIPNONE

Includes all cells specified in expList, regardless of their content, during calculation of the standard deviation.

SKIPMISSING

Excludes all #MISSING values from expList during calculation of the standard deviation.

SKIPZERO

Excludes all zero (0) values from expList during calculation of the standard deviation.

SKIPBOTH

Excludes all zero (0) values and #MISSING values from expList during calculation of the standard deviation.

expList

Comma-delimited list of member specifications, variable names, functions, or numeric expressions. expList provides a list of numeric values across which the standard deviation is calculated.

Notes

The @STDEV function replaces the @STDDEV function. The only difference between the functions is the SKIP parameter in the @STDEV function. Although the old @STDDEV function is supported for migration purposes, you can no longer select it in the Calculation Script Editor or Formula Editor.

Example

The following example is based on the Sample Basic database. Assume that the Measures dimension contains an additional member, Std Deviation. This example calculates the standard deviation (based on a sample of a population) of the sales values for all products and uses the @RANGE function to generate expList.

FIX (Product)
"Std Deviation" = @STDEV(SKIPBOTH,@RANGE(Sales,@CHILDREN(Product)));
ENDFIX

This example produces the following report:

                               Jan      New York
                              Actual      Budget
                              ======      ====== 
Sales          Colas           678         640
               Root Beer       551         530
               Cream Soda      663         510
               Fruit Soda      587         620
               Diet Drinks     #MI         #MI
                 Product      2479        2300

Std Deviation  Product          60.73       64.55

See Also