Representational Transfer Learning for Matrix Completion
Yong He, Zeyu Li, Dong Liu, Kangxiang Qin, Jiahui Xie
TL;DR
The paper tackles matrix completion under noise by leveraging multiple related sources through representational transfer learning. It formalizes representational similarity as containment of left and right singular subspaces, enabling a two-stage strategy: (i) unsupervised subspace integration across sources to learn shared $U$ and $V$, and (ii) a low-dimensional regression in the reduced space to estimate the target $\Theta_0^*$. The authors provide oracle theory giving near-optimal convergence rates and post-transfer inference, and propose a non-oracle procedure with selective subspace integration and optional knowledge transfer to avoid negative transfer. Simulations and real-data experiments (e.g., COVID-19 CT images) demonstrate robustness and practical gains over baseline methods, highlighting the approach’s efficiency and scalability for streaming data and potential tensor extensions.
Abstract
We propose to transfer representational knowledge from multiple sources to a target noisy matrix completion task by aggregating singular subspaces information. Under our representational similarity framework, we first integrate linear representation information by solving a two-way principal component analysis problem based on a properly debiased matrix-valued dataset. After acquiring better column and row representation estimators from the sources, the original high-dimensional target matrix completion problem is then transformed into a low-dimensional linear regression, of which the statistical efficiency is guaranteed. A variety of extensional arguments, including post-transfer statistical inference and robustness against negative transfer, are also discussed alongside. Finally, extensive simulation results and a number of real data cases are reported to support our claims.
