What is L2 regularization?
Updated May 15, 2026
Short answer
L2 adds squared penalty to weights in cost function.
Deep explanation
It discourages large weights and improves generalization.
Real-world example
Used in ridge regression models.
Common mistakes
- Confusing L2 with L1 sparsity effect.
Follow-up questions
- What is ridge regression?
- Does L2 set weights to zero?