A statistic, also called a sample statistic, is any quantity computed from values in a sample which is considered for a statistical purpose. The cited article says statistical purposes include estimating a population parameter, describing a sample or evaluating a hypothesis, that the average or mean of sample values is a statistic, and that the term is used both for the function, such as a calculation method of the average, and for the value of the function on a given sample, such as the result of the average calculation. Objects recorded in the atlas as statistics are grouped under this concept.