Regression Modeling Strategies: With Applicatio... -

Harrell’s primary mission is to combat . He argues against common but flawed practices like: Using P-values to select variables (Stepwise regression). Dropping "insignificant" variables from a final model.

Provides clear rules of thumb (like the 15-to-1 ratio) for how many variables a dataset can actually support. ⚖️ The Verdict

It bridges the gap between high-level theory and "boots-on-the-ground" data analysis. It teaches you how to build models that actually replicate in the real world.