Joshua earned an MBA from USF and writes mostly about software and technology.
The Purpose of the FISHER Function
The FISHER function gives an Excel user the ability to complete a Fisher z transformation easily. The Fisher z transformation is a calculation that will transform Pearson’s correlation coefficient. The transformation from (r to zr) is used to calculate a confidence interval for specifically for the Pearson’s correlation coefficient.
The equation of the Fisher z transformation formula is z = ln((1+r) / (1-r)) / 2. You can also seen an alternate form of this equation illustrated below.
The FISHER Function Syntax
The FISHER function needs to be inputted into a cell like a formula for it work. To manually add this function the following steps need to be taken:
- A cell needs clicked type "=FISHER(".
- After the open parenthesis the enter the correlation coefficient (r in the equation above)
- Lastly, use closed parenthesis and enter the formula.
Below in bold the simple syntax of the FISHER function is shown in its entirety.
X - The correlation coefficient. A number less than 1, but greater than or equal to zero. Using a number outside of this range or entering text into this function will cause and error. Note: This function only serves as a step to calculating a confidence interval.
Inserting the FISHER Function
The FISHER function can be inserted into a cell by first selecting a cell followed by clicking on the formula tab. Next, click on the more functions button and choose the FISHER function from the statistical function list.
After the formula builder appears, add the correlation coefficient. Notice the formula builder provides tips for creating the function.
Entering a confidence coefficient of .67 results in .81074 as shown below.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2022 Joshua Crowder