Harmonic Mean - Relationship With Other Means

Relationship With Other Means

If a set of non-identical numbers is subjected to a mean-preserving spread — that is, two or more elements of the set are "spread apart" from each other while leaving the arithmetic mean unchanged — then the harmonic mean always decreases.

Let r be a non zero real number and let the rth power mean ( Mr ) of a series of real variables ( a1, a2, a3, ... ) be defined as

For r = -1, 1 and 2 we have the harmonic, the arithmetic and the quadratic means respectively. Define r = 0, -∞ and +∞ to be the geometric mean, the minimum of the variates and the maximum of the variates respectively. Then for any two real numbers s and t such that s < t we have

with equality only if all the ai are equal.

Let R be the quadratic mean (or root mean square). Then

Read more about this topic:  Harmonic Mean

Famous quotes containing the words relationship with, relationship and/or means:

    Christianity as an organized religion has not always had a harmonious relationship with the family. Unlike Judaism, it kept almost no rituals that took place in private homes. The esteem that monasticism and priestly celibacy enjoyed implied a denigration of marriage and parenthood.
    Beatrice Gottlieb, U.S. historian. The Family in the Western World from the Black Death to the Industrial Age, ch. 12, Oxford University Press (1993)

    Strange and predatory and truly dangerous, car thieves and muggers—they seem to jeopardize all our cherished concepts, even our self-esteem, our property rights, our powers of love, our laws and pleasures. The only relationship we seem to have with them is scorn or bewilderment, but they belong somewhere on the dark prairies of a country that is in the throes of self-discovery.
    John Cheever (1912–1982)

    To say then, the majority are wicked, means no malice, no bad heart in the observer, but, simply that the majority are unripe, and have not yet come to themselves, do not yet know their opinion.
    Ralph Waldo Emerson (1803–1882)