juniorCurse of Dimensionality
How does adding features affect model performance?
Updated May 15, 2026
Short answer
It can improve or degrade performance depending on relevance.
Deep explanation
Irrelevant features increase noise and sparsity, while relevant features can improve signal strength. High dimensionality amplifies both effects.
Real-world example
Adding thousands of user behavior features in recommendation systems.
Common mistakes
- Assuming more features always help.
Follow-up questions
- What is feature redundancy?
- How to filter features?