The STANDARD-DEVIATION function returns a numeric value that approximates the standard deviation of its arguments. The type of this function is numeric.
Usage
FUNCTION STANDARD-DEVIATION ({argument-1} ... )
Parameters
Argument-1 must be class numeric.
Returned Values
1. The returned value is the approximation of the standard deviation of the argument-1 series.
2. The returned value is calculated as follows:
a) The difference between each argument-1 value and the arithmetic mean of the argument-1 series is calculated and squared.
b) The values obtained are then added together. This quantity is divided by the number of values in the argument-1 series.
c) The square root of the quotient obtained is then calculated. The returned value is the absolute value of the square root.
3. If the argument-1 series consists of only one value, or if the argument-1 series consists of all variable occurrence data items and the total number of occurrences for all of them is one, the returned value is zero.