the second moment around the mean; the expected value of the square of the deviations of a random variable from its mean value

a branch of applied mathematics concerned with the collection and interpretation of quantitative data and the use of probability theory to estimate population parameters

(probability and statistics) the average distance of a random variable from the mean value, equal to the square root of its variance.

the standard deviation of an entire statistical population.

the standard deviation of a random sample taken from a statistical population.

the standard deviation of points formed around a linear function, and an estimate of the accuracy of the dependent variable being measured.

a branch of applied mathematics concerned with the collection and interpretation of quantitative data and the use of probability theory to estimate population parameters