A measure of central tendency in statistics, describing a value's frequency.
In testing, norms are figures describing the frequency with which particular scores appear. They provide information about whether a score is above or below average and about what percentage of the persons tested received that score. Norms may apply to tests of mental ability or achievement, such as IQ tests or SATs. They are also used in personality assessment to measure variables such as anxiety, introversion-extroversion, and paranoia. The term "norm" may also refer to social norms, unwritten social rules that define acceptable and unacceptable behavior in a variety of situations.