R-squared - Yousef's Notes
R-squared

R-squared

A statistical measure indicating the proportion of variance in the dependent variable that is predictable from the independent variables.

  • Range: Typically between 0 and 1.

#Interpretation

  • 0: Model explains none of the variability.
  • 1: Model explains all the variability.

#Purpose

Assesses goodness-of-fit in regression models; higher values suggest a better fit, though context matters.

#Limitations

  • Does not indicate causality.
  • Can be misleading with non-linear relationships or overfitting.
  • Sensitive to the number of predictors: adding variables may increase R-squared even if they don’t improve predictive power.

#Complementary measures

Adjusted R-squared accounts for model complexity, providing a more accurate assessment in models with multiple predictors.