Multiple Regression for Matrix and Vector Predictors: Models, Theory, Algorithms, and Beyond
Meixia Lin, Ziyang Zeng, Yangjing Zhang
TL;DR
The paper studies regression where responses depend on both matrix predictors $X_i$ and vector predictors $z_i$ through $y_i \approx \langle X_i,B\rangle + \langle z_i,\gamma\rangle$, and introduces a general convex regularized framework with penalties such as $\phi(B)=\rho\|B\|_*$ and $\psi(\gamma)=\lambda\|\gamma\|_1$. It develops a preconditioned proximal point algorithm (PPA) whose dual problem $\Phi_k(\xi)$ is differentiable with Lipschitz gradient and can be solved by a semismooth Newton method, exploiting second-order sparsity to update the primal variables via proximal maps. The main contributions are (i) finite-sample consistency results ($n$-consistency and $\sqrt{n}$-consistency) under nuclear and $\ell_1$ penalties, (ii) a scalable, robust solver that leverages second-order information, and (iii) extensive empirical evidence showing improved estimation, prediction accuracy, and computational efficiency over ADMM and Nesterov methods on both synthetic and COVID-19 data. The framework extends to other convex losses (and potentially to logistic/Poisson) and offers a path toward efficient handling of high-dimensional matrix–vector regression problems with structured penalties in real-world multivariate data analysis.
Abstract
Matrix regression plays an important role in modern data analysis due to its ability to handle complex relationships involving both matrix and vector variables. We propose a class of regularized regression models capable of predicting both matrix and vector variables, accommodating various regularization techniques tailored to the inherent structures of the data. We establish the consistency of our estimator when penalizing the nuclear norm of the matrix variable and the $\ell_1$ norm of the vector variable. To tackle the general regularized regression model, we propose a unified framework based on an efficient preconditioned proximal point algorithm. Numerical experiments demonstrate the superior estimation and prediction accuracy of our proposed estimator, as well as the efficiency of our algorithm compared to the state-of-the-art solvers.
