Documentation/How Tos/Calc: LOGNORMDIST function

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 + 0.5 * ERF((LN(x)-μ)/(σ*SQRT(2)))

Example:

LOGNORMDIST(1; 0; 1)

returns 0.5.

See also:

LOGINV, NORMDIST, NORMSDIST, NORMSINV, NORMINV, ERF, LN, SQRT

Statistical functions

Issues:

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