What is Ridge Regression?

Updated May 16, 2026

Short answer

Ridge regression adds L2 regularization to reduce overfitting.

Deep explanation

It penalizes large coefficients by adding λ∑β² to the loss function. This shrinks coefficients but does not set them to zero, improving generalization and reducing multicollinearity impact.

Real-world example

Used in pricing models where many correlated features exist.

Common mistakes

  • Assuming ridge performs feature selection.

Follow-up questions

  • How does alpha affect model complexity?
  • When is ridge preferred over lasso?

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