Definition
Structural risk minimization (SRM) is a method for minimizing expected risk by controlling model complexity to prevent overfitting. It extends empirical risk minimization by adding a regularization term that penalizes complex models. SRM relies on the Vapnik-Chervonenkis (VC) dimension to define confidence intervals around empirical error. By selecting a model from a nested sequence of hypothesis spaces, SRM finds the optimal trade-off between fitting training data well and maintaining simplicity. This ensures better generalization performance on unseen data compared to simply minimizing training error.
Summary
A principle in statistical learning that seeks to minimize the upper bound of the generalization error by balancing model fit and complexity.
Key Concepts
- VC dimension
- Regularization
- Generalization error
- Model complexity penalty
Use Cases
- Support Vector Machine (SVM) training
- Selecting polynomial degree in regression
- Pruning decision trees to avoid overfitting