In Excel 2010, the TINV function has been replaced by the T.INV.2T function.
The Excel TINV function calculates the inverse of the two-tailed Student's T Distribution, which is a continuous probability distribution that is frequently used for testing hypotheses on small sample data sets.
The syntax of the function is:
Where the function arguments are:
|probability||-||The probability (between 0 and 1) for which you want to evaluate the inverse of the two-tailed Student's T Distribution.|
|degrees_freedom||-||The number of degrees of freedom (must be ≥ 1).|
The above chart on the right shows the 2-tailed Inverse Student's T Distribution with 10 degrees of freedom.
If you want to calculate the value of this function for a probability of 0.25, this can be done using the Excel Tinv function, as follows:
This gives the result 1.221255395.
If you want to calculate the value of the one-tailed inverse Student's T-Distribution for a probability of 0.25, this can be done by doubling the probability, as follows:
This gives the result 0.699812061.
Further information and examples of the Excel Tinv function are provided on the Microsoft Office website.
If you get an error from the Excel Tinv function this is likely to be one of the following:
|#VALUE!||-||Occurs if one or both of the supplied arguments are non-numeric.|