Fisher Transformation - Definition

Definition

The transformation is defined by:

where "ln" is the natural logarithm function and "artanh" is the inverse hyperbolic function.

If (X, Y) has a bivariate normal distribution, and if the (Xi, Yi) pairs used to form r are independent for i = 1, ..., n, then z is approximately normally distributed with mean

and standard error

where N is the sample size.

This transformation, and its inverse,

can be used to construct a confidence interval for ρ.

Read more about this topic:  Fisher Transformation

Famous quotes containing the word definition:

    The physicians say, they are not materialists; but they are:MSpirit is matter reduced to an extreme thinness: O so thin!—But the definition of spiritual should be, that which is its own evidence. What notions do they attach to love! what to religion! One would not willingly pronounce these words in their hearing, and give them the occasion to profane them.
    Ralph Waldo Emerson (1803–1882)

    No man, not even a doctor, ever gives any other definition of what a nurse should be than this—”devoted and obedient.” This definition would do just as well for a porter. It might even do for a horse. It would not do for a policeman.
    Florence Nightingale (1820–1910)

    One definition of man is “an intelligence served by organs.”
    Ralph Waldo Emerson (1803–1882)