**Empirical rule, **

### Definition of Empirical rule:

In particular, the empirical rule predicts that 68% of observations falls within the first standard deviation (µ ± σ), 95% within the first two standard deviations (µ ± 2σ), and 99.7% within the first three standard deviations (µ ± 3σ).

Used in statistics, the rule states that for a normal distribution almost all of the values will be within 3 standard deviations of the mean. Also called 68-95-99.7 rule or three sigma rule.

The empirical rule, also referred to as the three-sigma rule or 68-95-99.7 rule, is a statistical rule which states that for a normal distribution, almost all observed data will fall within three standard deviations (denoted by σ) of the mean or average (denoted by µ).

### How to use Empirical rule in a sentence?

- Three-sigma limits that follow the Empirical Rule are used to set the upper and lower control limits in statistical quality control charts and in risk analysis such as VaR.
- The Empirical Rule states that 99.7% of data observed following a normal distribution lies within 3 standard deviations of the mean.
- Under this rule, 68% of the data falls within one standard deviation, 95% percent within two standard deviations, and 99.7% within three standard deviations from the mean.

Meaning of Empirical rule & Empirical rule Definition