Coefficient of determination

In statistics, the coefficient of determination, denoted R or r and pronounced R squared, is a number that indicates the proportion of the variance in the dependent variable that is predictable from the independent variable.

It is a statistic used in the context of statistical models whose main purpose is either the prediction of future outcomes or the testing of hypotheses, on the basis of other related information. It provides a measure of how well observed outcomes are replicated by the model, based on the proportion of total variation of outcomes explained by the model (pp. 187, 287).