Difference between revisions of "Documentation/How Tos/Calc: LOGNORMDIST function"

CALC FUNCTIONS
FUNCTIONS
Measures of Central Tendency
Probability and statistics
Correlation and line fitting
Ranking

LOGNORMDIST

Calculates values for the cumulative distribution function of a lognormal distribution.

Syntax:

LOGNORMDIST(x; μ; σ;)

A variable is lognormally distributed if its natural logarithm is normally distributed. Parameters of the distribution are μ (mean) and σ (standard deviation).
LOGNORMDIST calculates the cumulative density function for a lognormal distribution.
LOGNORMDIST(x; μ; σ;) is equivalent to NORMDIST((LN(x)-μ)/σ; 0; 1; 1); it may also be calculated from
0.5 * ERFC((-LN(x)+μ)/(σ*SQRT(2)))
The function ERFC belongs to the category Add-in.

Example:

LOGNORMDIST(1; 0; 1)

returns 0.5.

Issues:

• In the forthcoming international standard ODFF this function has an extra parameter, allowing calculation of the probability density function as well.
Template:Documentation/SeeAlso