In probability theory, a log-normal (or lognormal) distribution is a continuous probability distribution of a random variable whose logarithm is normally distributed.

May 21, 2025 · As a data practitioner, you’ll often encounter data that looks almost normal but has a stubborn right tail that stretches way out. Stock prices, web session times, income distributions, and …

It models phenomena whose relative growth rate is independent of size, which is true of most natural phenomena including the size of tissue and blood pressure, income distribution, and even the length …

What is a lognormal distribution? A lognormal distribution is one where the logarithm of the variable of interest is normally distributed. Consequently, the lognormal variable itself is strictly positive (i.e., >0) …

The lognormal distribution is used extensively in reliability applications to model failure times. The lognormal and Weibull distributions are probably the most commonly used distributions in reliability …

Feb 16, 2022 · The log-normal distribution is a right skewed continuous probability distribution, meaning it has a long tail towards the right. It is used for modelling various natural phenomena such as …

Dec 22, 2025 · A log normal distribution results if the variable is the product of a large number of independent, identically-distributed variables in the same way that a normal distribution results if the …

Aug 23, 2025 · What Is a Log-Normal Distribution? A log-normal distribution represents a set of data that follows a normal distribution when logarithms are applied to its values.

What is the Lognormal Distribution? The lognormal distribution is a continuous probability distribution that models right-skewed data. The unimodal shape of the lognormal distribution is comparable to …

Log-normal random variables are characterized as follows. Definition Let be a continuous random variable. Let its support be the set of strictly positive real numbers: We say that has a log-normal …