Math: Regularization

Machine-learning ideas tagged Regularization in the Math taxonomy of the Math2NN corpus.

△ Mechanism confirmed, baseline not beaten 2026

CVaR-tail active residual correction

Train a cheap neural surrogate globally, then use an ensemble or bootstrap covariance to identify inputs near the estimated upper-tail boundary and inputs where high-fidelity correction is uncertain. Fit a Tikhonov-regularized residual model on the acquired expensive labels and use the corrected predictor for CVaR estimation or risk-constrained optimization. The acquisition policy deliberately ignores easy central-region samples unless they influence the tail threshold.

Useful7/10
Difficulty5/10
Novelty6/10
Paper: Risk-averse design optimization with CVaR constraints via multifidelity tail-region correction arXiv:2608.29222
△ Mechanism confirmed, baseline not beaten 2026

Shared-Private Matrix-Weighted Expert Layers

Build a multi-expert or multi-task layer whose feature channels are divided into a globally shared subspace and expert-private subspaces. Matrix-weighted message passing couples experts only through selected feature directions, while the nullspace preserves specialization; the graph-cut condition provides a concrete test that the shared channels can propagate across all experts rather than becoming disconnected islands.

Useful7/10
Difficulty6/10
Novelty7/10
Paper: Subspace Consensus of Matrix-Weighted Networks arXiv:2607.06970