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:

    It’s a rare parent who can see his or her child clearly and objectively. At a school board meeting I attended . . . the only definition of a gifted child on which everyone in the audience could agree was “mine.”
    Jane Adams (20th century)

    Perhaps the best definition of progress would be the continuing efforts of men and women to narrow the gap between the convenience of the powers that be and the unwritten charter.
    Nadine Gordimer (b. 1923)

    I’m beginning to think that the proper definition of “Man” is “an animal that writes letters.”
    Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)