Table 4. Conversion from various statistics to Perason r correlation coefficient association measures3.

Statistic	Conversion formula	Comment
χ2df = 1	$$\mathit{r}=\sqrt{\frac{{\mathrm{\chi }}^2\mathit{\text{df}}=1}{\mathit{N}}}$$	A single degree of freedom chi-square value divided by the number of cases
t	$$\mathit{r}=\sqrt{\frac{{\mathit{t}}^2}{{\mathit{t}}^2+\mathit{\text{df}}}}$$	From t value to r correlation coefficient
F	$$\mathit{r}=\sqrt{\frac{\mathit{F}\left(\mathit{\text{df}}=\mathrm{1},\_\right)}{\mathit{F}\left(\mathit{\text{df}}=\mathrm{1},\_\right)+\mathit{\text{df}}\left(\mathit{\text{error}}\right)}}$$	From F value with single freedom numerator to r
Cohen's d	$$\mathit{r}=\sqrt{\frac{{\mathit{d}}^2}{{\mathit{d}}^2+\mathrm{\text{4}}}}$$	From Cohen's d to r