# Log Normal Distribution

**Log Normal Statistical Distribution**

**General Characteristics**

- Log Normal distribution is also referred to as Gibrat distribution, Galton’s distribution, McAlister distribution or Cobb-Douglas distribution.

- A positive variable X is Log-Normally distributed if its Logarithm is normally distributed.

**Specific Characteristics**

**Key Measures:
**

Location, Spread

**Range of values:**

0 < x < ∞

**Mean:**

Mean = e ^ (location + (spread /2))

**Standard Deviation, SD:**

SD = √[(e^((2location) + spread)) * ((e^(spread)) – 1)]

**Application**

Log Normal distributions can be used to calculate the time required to complete a task.

**Log Normal Statistical Distribution – Statistical Distributions**

**Education | thetqweb**