A note on shrinkage regularization in semi-parametric regression trees
摘要
This study introduces a novel shrinkage regularization approach for semi-parametric regression trees, combining the strengths of parametric and nonparametric methods to enhance predictive performance and adaptability. The proposed method integrates weighted regression with regularization penalties, leveraging prior estimations and data-driven weighting schemes to mitigate multicollinearity and overfitting. We evaluate the model alongside classical techniques (Ridge, LASSO, Elastic Net) in both parametric and semi-parametric frameworks, incorporating regression trees for nonparametric components. Simulation studies and real-world datasets (Liver Disorders and Computer Hardware) demonstrate the superior performance of the proposed method, particularly in handling multicollinearity and capturing nonlinear relationships. Results show significant improvements in predictive accuracy, as measured by