The arithmetic mean is a measure of central tendency, and like all measures of central tendency, it is used to identify a single numerical value that is most “typical” or representative of a data set. Commonly referred to as the “average” or simply the “mean,” the arithmetic mean identifies the numerical average of all values in a data set. It is one of the three most well-known measures of central tendency, along with the median (the middle value) and the mode (the most frequent value), and is the most often used. The arithmetic [Page 933]mean is useful both as a descriptive statistic and as an inferential statistic. In addition, it is used in calculations for many other statistical processes. The arithmetic mean is calculated by ...