In practice, most statisticians and researchers prefer to use r2, the coefficient of determination as a measure of strength as it represents the proportion or percentage of the variability of \...In practice, most statisticians and researchers prefer to use r2, the coefficient of determination as a measure of strength as it represents the proportion or percentage of the variability of Y that is explained by the variability of X. We can also calculate the correlation coefficient (r) by taking the appropriate square root of r2, depending on whether the estimate of the slope (b1) is positive or negative:
