R² measures the proportion of variation in a regression response explained collectively by its predictors. Values range from 0 to 1: 0 explains none of the variation, while 1 explains it all. section 5.7.3
Predicting NBA wins
For the fit1 model, glance(fit1) returns R² = 0.202 and adjusted R² = 0.137. The predictors therefore explain about 20% of variation in regular-season wins, but the adjusted measure suggests about 14% after accounting for model complexity. The model’s average absolute prediction error is 8.27 wins. section 5.7.3






