This fact is sometimes called the "empirical rule," a heuristic that describes where most of the data in a normal distribution will appear. Data falling outside three standard deviations ("3-sigma ...

The Empirical Rule describes how to visualize the individual values of your data across a normal curve. It will be based on the mean and standard deviation of your data. This is shown below.

The bell curve, or normal distribution, occurs throughout statistics. Like snowflakes, ... This relationship is known as the 68-95-99.7 rule (or the empirical rule).

The empirical rule shows that 68% of the distribution lies within one standard deviation, in this case, from 11.6 to 14.6 years. Thus, the remaining 32% of the distribution lies outside this range.

goodness-of-fit tests based on the empirical distribution function (EDF): the Anderson-Darling, Cramer-von Mises, and Kolmogorov-Smirnov tests. The p-values for these tests are smaller than the usual ...