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→Other measures of central tendency
Because of these characteristics, an average takes a group of numbers and replaces it with a single number that can be thought of as the center of the group, or as a representative value that can stand for the whole group.
Because of these characteristics, an average takes a group of numbers and replaces it with a single number that can be thought of as the center of the group, or as a representative value that can stand for the whole group.
The average is ''not'' the only way to do this. It is one of a number of ''measures of central tendency.'' All of them replace a group of numbers with a single number that falls somewhere within the group.
The average is ''not'' measurement with these characteristics. It is one of a number of ''measures of central tendency.'' All of them replace a group of numbers with a single number that falls somewhere within the group.
Because the average is familiar and easily calculated, it is often chosen as the single number that summarizes a group. Depending on how the number is to be used, sometimes the average is a good choice, sometimes it is not, so it is important to understand the other choices.
Because the average is familiar and easily calculated, it is often chosen as the single number that summarizes a group. Depending on how the number is to be used, sometimes the average is a good choice, sometimes it is not, so it is important to understand the other choices.
**The [[harmonic mean]] is used when averaging speeds that are all measured along the same distance (rather than the same time).
**The [[harmonic mean]] is used when averaging speeds that are all measured along the same distance (rather than the same time).
**The [[root mean square]] is used in engineering power calculations, and heavily used in statistics in measurements of [[variance]].
**The [[root mean square]] is used in engineering power calculations, and heavily used in statistics in measurements of [[variance]].
==The average as a "balance point"==
==The average as a "balance point"==