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:

    Guilty, guilty, guilty is the chant divorced parents repeat in their heads. This constant reminder remains just below our consciousness. Nevertheless, its presence clouds our judgment, inhibits our actions, and interferes in our relationship with our children. Guilt is a major roadblock to building a new life for yourself and to being an effective parent.
    Stephanie Marston (20th century)

    Most childhood problems don’t result from “bad” parenting, but are the inevitable result of the growing that parents and children do together. The point isn’t to head off these problems or find ways around them, but rather to work through them together and in doing so to develop a relationship of mutual trust to rely on when the next problem comes along.
    Fred Rogers (20th century)

    Hope is a bad thing. It means that you are not what you want to be. It means that part of you is dead, if not all of you. It means that you entertain illusions. It’s a sort of spiritual clap, I should say.
    Henry Miller (1891–1980)