The empirical rule (also called the "68-95-99.7 rule") is a guideline for how data is distributed in a normal distribution.The rule states that (approximately):- 68% of the data points will fall within one standard deviation of the mean. - 95% of the data points will fall within two standard deviations of the mean. - 99.7% of the data points will fall within three standard deviations of the mean.
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