Documentation/Calc Functions/FISHERINV

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    Function name:

    FISHERINV

    Category:

    Statistical Analysis

    Summary:

    Calculates the inverse of the Fisher transformation for a given number. [math]\displaystyle{ \text{FISHERINV}(z) }[/math] returns the value r, such that [math]\displaystyle{ \text{FISHER}(r)~=~z }[/math].

    Syntax:

    FISHERINV(Number)

    Returns:

    Returns a real number, which is the correlation coefficient that when Fisher-transformed gives a specified value.

    Arguments:

    Number is a real number, or a reference to a cell containing that number, which is the value to undergo the inverse transformation back to a correlation coefficient.

    • If Number is non-numeric, then FISHER reports a #VALUE! error.

    Additional details:

    • The formula for the FISHERINV function is:
    [math]\displaystyle{ \text{FISHERINV}(z)~=~\frac{e^{2z}-1}{e^{2z}+1} }[/math]
    where z is the Fisher-transformed value to be converted back to a correlation coefficient.
    • FISHERINV utilizes the same formula as the TANH function.
    • The figure below illustrates the FISHERINV function:
    Inverse fisher transformation plot.png

    Examples:

    Formula Description Returns
    =FISHERINV(A1) where cell A1 contains the value -1.09861228866811. Here the formula calculates the correlation coefficient that when Fisher-transformed yields the result -1.09861228866811. -0.8
    =FISHERINV(0) Here the formula calculates the correlation coefficient that when Fisher-transformed yields the result 0. 0
    =FISHERINV(1.09861228866811) Here the formula calculates the correlation coefficient that when Fisher-transformed yields the result 1.09861228866811. 0.8

    Related LibreOffice functions:

    FISHER

    TANH

    ODF standard:

    Section 6.18.27, part 2

    Related (or similar) Excel functions:

    FISHERINV