106 High-Function Business Intelligence in e-business
An example of standard deviation is shown in “STDDEV examples” on page 113.
3.2.10 SUM
The SUM function returns the sum of a set of numbers. The function is applied to
the set of values derived from the argument values by the elimination of null
values.
If the function is applied to an empty set, the result is a null value. Otherwise, the
result is the sum of the values in the set.
3.2.11 VARIANCE
The VARIANCE function returns the population variance (as opposed to the
sample variance) of a set of numbers.
The relationship between population variance (Var
pop
) and sample variance
(Var
samp
) is as follows:
Where:
n is the population size.
The argument values must be numeric.
The function is applied to the set of values derived from the argument values by
the elimination of null values.
If the function is applied to an empty set, the result is a null value.
An example of variance is shown in, “VARIANCE example” on page 113.
Var
pop
n
1–()
n
-----------------
Var
samp
×=
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