16 Random formulas

These formulas will eventually move somewhere that makes sense but for now they need a home and this is it:

16.1 t-value to r-value

Did you know that the conversion of a t-value to an r-value is:

\[r = \sqrt\frac{t^2}{t^2 + df}\]

And the conversion of an r-value to a t-value is:

\[t = \sqrt\frac{df * r^2}{1-r^2}\]

Where in both formulas, the \(df\) is the degrees of freedom of the respective analysis that has been carried out. For example, if you have carried out a correlation and have an r-value but want the t-value, use the df of the correlation to make the conversion. Likewise, if you have carried out a t-test and you want the r-value, use the df of the t-test to make the conversion.