Asked by: Almike Palicio
business and finance business operations

What percentage of the data is within 2 standard deviations of the mean?

Last Updated: 29th June, 2020

For an approximately normal data set, the valueswithinone standard deviation of the mean account for about68% ofthe set; while within two standard deviations accountfor about95%; and within three standard deviations account forabout99.7%.

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Hereof, what percentage of the data falls within 2 standard deviation of the mean?

95.4 percent

Secondly, what percent of values lie beyond 2 standard deviations of the mean? 95 percent

In respect to this, what is 2 standard deviations from the mean?

Standard Deviation. Specifically, if a set ofdatais normally (randomly, for our purposes) distributed aboutitsmean, then about 2/3 of the data values willliewithin 1 standard deviation of the mean value,andabout 95/100 of the data values will lie within 2standarddeviations of the mean value.

What percent of observations are between the mean and two standard deviations above the mean in a normal distribution?

Regardless of what a normal distributionlookslike or how big or small the standard deviationis,approximately 68 percent of the observations (or68percent of the area under the curve) will alwaysfallwithin two standard deviations (one above andonebelow) of the mean.

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