# 68–95–99.7 rule

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## Definition of the noun 68–95–99.7 rule

What does 68–95–99.7 rule mean as a name of something?

**noun**

- [
*statistics*] That a normal distribution has 68% of its observations within one standard deviation of the mean, 95% within two, and 99.7% within three.- synonym: empirical rule

## Explanation

**68–95–99.7 rule**: In statistics, the 68–95–99.7 rule, also known as the three-sigma rule or empirical rule, states that nearly all values lie within three standard deviations of the mean in a normal distribution.

- also known as 68-95-99.7 rule

## Printed encyclopedias and other books with definitions for 68–95–99.7 rule

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### Encyclopedia of Mathematics (2005)

by James Stuart Tanton

From the study of the NORMAL
DISTRIBUTION, **the 68–95–99.7 rule** states that 95 percent of the measurements
...

## Online dictionaries and encyclopedias with entries for 68–95–99.7 rule

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## Quotes about 68–95–99.7 rule

Rule A: Don't. Rule A1: Rule A doesn't exist. Rule A2: Do not discuss the existence or non-existence of Rules A, A1 or A2. (R.D. Laing)*more quotes...*