arXiv Machine Learning

Joint Bayesian Parameter and Model Order Estimation for Low-Rank Probability Mass Tensors

arXiv:2410. 06329v4 Announce Type: replace-cross Abstract: Obtaining a reliable estimate of the joint probability mass function (PMF) of a set of random variables from observed data is a significant objective in statistical signal processing and machine learning.

arXiv Machine Learning
Jun 4

Low-rank Distributional Matrix Completion

arXiv:2606. 04176v1 Announce Type: new Abstract: We study a distributional generalization of the matrix completion problem in which each entry of the target matrix is a probability distribution rather than a scalar.

By Jiayi Wang, Raymond K. W. Wong
arXiv AI
Sep 4

LLM Evaluation as Tensor Completion: Low Rank Structure and Semiparametric Efficiency

The paper treats large language model (LLM) evaluation as a tensor completion problem, modeling noisy, sparse, and non‑uniform pairwise human judgments through a low‑rank latent score tensor under Bradley‑Terry‑Luce‑type models. It derives the efficient influence function and semiparametric efficiency bound for smooth functionals of the true tensor, and proposes a one‑step debiased estimator with asymptotic normality. A key innovation is a score‑whitening technique that equalizes local Fisher information, overcoming anisotropy in the information operator and enabling stable inference at optimal sample‑complexity.

By Jiachun Li, David Simchi-Levi, Will Wei Sun
arXiv Machine Learning
Aug 6

E$^2$M: Double Bounded $\alpha$-Divergence Optimization for Tensor-based Discrete Density Estimation

arXiv:2405. 18220v4 Announce Type: replace-cross Abstract: Tensor-based discrete density estimation requires flexible modeling and proper divergence criteria to enable effective learning; however, traditional approaches using $\alpha$-divergence face analytical challenges due to the $\alpha$-power terms in the objective function, which hinder the derivation of closed-form update rules.

By Kazu Ghalamkari, Jesper L{\o}ve Hinrich, Morten M{\o}rup
arXiv Machine Learning
Sep 11

RiVaT-Fuse: Reliability-Calibrated Variational Tensor Fusion for Multimodal Prediction under Modality Uncertainty

RiVaT‑Fuse introduces a reliability‑calibrated variational tensor fusion framework for multimodal image‑metadata prediction, treating fusion as a sample‑wise latent‑state estimation rather than simple aggregation. It replaces scalar modality confidence with matrix‑valued trust geometry, decomposes interactions into additive, multiplicative, and relational components, and couples the latent state with conditional robustness and structured multi‑task prediction. On an image‑level benchmark, RiVaT‑Fuse outperforms direct representation‑level baselines and improves probability and label stability under perturbation.

By Yingfan Xu, Tieming Liu, Ye Liang, Taiping Liu
arXiv AI
Jul 28

Bayesian-LoRA: Probabilistic Low-Rank Adaptation of Large Language Models

arXiv:2601. 21003v3 Announce Type: replace Abstract: Large Language Models usually put more emphasis on accuracy and therefore, will guess even when not certain about the prediction, which is especially severe when fine-tuned on small datasets due to the inherent tendency toward miscalibration.

By Moule Lin, Shuhao Guan, Andrea Patane, David Gregg, Goetz Botterweck
arXiv Machine Learning
Jun 30

BaRA: Bayesian Adaptive Rank Allocation for Parameter-Efficient Fine-Tuning

arXiv:2606. 29184v1 Announce Type: new Abstract: While Low-rank adaptation (LoRA) enables highly efficient fine-tuning by constraining task-specific updates to fixed low-rank subspaces, this rigid design limits representational flexibility and often results in overconfident predictions and miscalibrated uncertainty, especially in low-data regimes.

By Zhibin Duan, Yuhong Wang, Jiahong Fu, Zongsheng Yue, Bo Chen, Zongben Xu