ML: Representation

Machine-learning ideas tagged Representation in the ML taxonomy of the Math2NN corpus.

Unverified 2026

Mixed-Type Conditional-Invariance Regularizer

Use the paper's coarse-versus-fine neighborhood comparison as a differentiable penalty on a neural representation. For each sample, compare similarity of target or sensitive-variable embeddings among points close in context Z alone against points close in (Z,R), where R=f_theta(X) is the learned representation. Under conditional independence, adding R should not increase local similarity, so the network is penalized when the fine-neighborhood statistic differs systematically from the coarse one.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: MixCIT: A Kernel Based Local-Polynomial Debiased Test for Conditional Independence on Mixed-Type Data arXiv:2607.12830
Unverified 2026

Post-Fixing Orthogonality Regularizer

Add a graph-derived conditional moment penalty to a neural representation or predictor. For each nested Markov constraint represented after fixing variables in R, residualize functions of (X,Z) with respect to Z under the post-fixing distribution and penalize their weighted correlation with functions of (Y,Z). This directly targets the equality constraint and can be more informative than an unconditional decorrelation penalty.

Useful5/10
Difficulty6/10
Novelty5/10
Paper: Toward a Semiparametric Efficiency Theory under Equality Constraints in Nested Markov Models arXiv:2608.24602