- noun a measure of the amount by which a set of values differs from the arithmetic mean
- A statistic, used as a measure of dispersion in a distribution, that is equal to the square root of the arithmetic average of the squares of the deviations from the mean.
- noun the measure of how much a variable changes from its mean
- A statistical measure of the dispersion or spread around the mean, for a given set, series, or population. It is equal to the square root of the variance. If a data set has as a bell-shaped distribution, for instance, 68.3% of the data will fall on either side of one standard deviation, 95.5% within two standard deviation, 99.7% within three, and so on. Its abbreviation is SD. Its symbol is σ.
Information & Library Science
- noun a statistical term to show how far things are different from the normal