arXiv AI

Neighborhood Elites: Quality-Diversity Search for Uncertainty Quantification in Question Answering

The paper introduces Neighborhood Elites (NE), a quality‑diversity search method for generating answer‑preserving rewrites in question answering. NE explicitly controls two dimensions—type of edit and explicitness of support—to create diverse perturbations that improve uncertainty quantification. Across five extractive‑QA datasets and five instruction‑tuned LLMs, NE outperforms other constructors, achieving higher AUROC and AUPRC scores and surpassing semantic entropy baselines.

Hugging Face Trending Papers
Oct 29

Neighborhood Elites: Quality-Diversity Search for Uncertainty Quantification in Question Answering

The paper introduces Neighborhood Elites (NE), a quality‑diversity search method that constructs input rewrites for large language models in question answering by controlling both the type of edit and the explicitness of support. NE outperforms three other neighborhood constructors across five extractive‑QA datasets and five instruction‑tuned LLMs, achieving higher AUROC and AUPRC scores and surpassing semantic entropy from decoder samples. The method demonstrates that carefully designed perturbations improve failure detection in QA systems.

arXiv AI
Sep 15

Drift-Constrained Optimization: Only Direction Matters in Fine-Tuning Instruct Models

The paper introduces Drift-Constrained Optimization (DCO), a framework that treats behavioral drift during fine‑tuning of instruction models as a bounded constraint rather than an uncontrolled side effect. By defining a drift budget, the authors reformulate fine‑tuning as a direction‑selection problem, showing that choosing different update directions can qualitatively change outcomes. Experiments on Qwen3 models demonstrate that carefully selected directions improve scientific reasoning and multilingual translation while preserving reasoning capabilities and general performance.

By Fei Yuan, Changjiang Gao, Yilei Tu, Yifeng Liu, Shujian Huang, Yu Qiao
arXiv Machine Learning
Aug 21

LODESTAR: Robust Entropy-Based Answer Selection in Retrieval-Augmented Generation for Question Answering -- Directing Frozen-LLM Entropy with a Reinforcement-Learned Prompt Polarizer under Misleading Passages

arXiv:2608. 11922v2 Announce Type: replace-cross Abstract: Predictive-distribution entropy is a strong answer-selection rule in retrieval-augmented generation (RAG) for question answering: across five QA benchmarks, selecting the answer a frozen respondent LLM produces with the lowest answer-token entropy lifts mean $F_1$ from 0.

By Hung-Chun Hsu, Po-Jen Ko, Che-Cheng Wu, Li-Yang Chang, Chuan-Ju Wang
arXiv Machine Learning
Aug 13

LODESTAR: Trustworthy Entropy Is Navigated, Not Merely Measured -- Reinforced Polarizer Keeps a Frozen LLM from Being Confidently Misled by the Wrong Evidence

arXiv:2608. 11922v1 Announce Type: cross Abstract: Predictive-distribution entropy makes a strong selection rule in retrieval-augmented question answering: across five QA benchmarks, keeping the candidate answer that a frozen respondent LLM produces with the lowest answer-token entropy lifts mean answer $F_1$ from 0.

By Po-Jen Ko, Che-Cheng Wu, Hung-Chun Hsu, Li-Yang Chang, Chuan-Ju Wang