๐ค AI Summary
This work proposes a novel approach that integrates principal componentโguided sparse regularization (pcLasso) into the reduced-rank regression framework, addressing a key limitation of existing methods which struggle to simultaneously exploit the principal component structure and group structure of predictors while effectively biasing regression coefficients toward high-variance principal component directions. By explicitly incorporating predictor principal component orientations, group information, and inter-response correlations, the proposed method overcomes constraints inherent in conventional models, enhancing both predictive accuracy and model interpretability. Extensive numerical simulations and real-data analyses demonstrate the substantial advantages of this approach in terms of prediction performance and explanatory power.
๐ Abstract
Reduced-rank regression estimates regression coefficients by imposing a low-rank constraint on the matrix of regression coefficients, thereby accounting for correlations among response variables. To further improve predictive accuracy and model interpretability, several regularized reduced-rank regression methods have been proposed. However, these existing methods cannot bias the regression coefficients toward the leading principal component directions while accounting for the correlation structure among explanatory variables. In addition, when the explanatory variables exhibit a group structure, the correlation structure within each group cannot be adequately incorporated. To overcome these limitations, we propose a new method that introduces pcLasso into the reduced-rank regression framework. The proposed method improves predictive accuracy by accounting for the correlation among response variables while strongly biasing the matrix of regression coefficients toward principal component directions with large variance. Furthermore, even in settings where the explanatory variables possess a group structure, the proposed method is capable of explicitly incorporating this structure into the estimation process. Finally, we illustrate the effectiveness of the proposed method through numerical simulations and real data application.