No-Worse Context-Aware Decoding: Preventing Neutral Regression in Context-Conditioned Generation

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Tao, Yufei, Agrawal, Ameeta
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914485630926848
author Tao, Yufei
Agrawal, Ameeta
author_facet Tao, Yufei
Agrawal, Ameeta
contents Large language models (LLMs) can answer questions and summarize documents when conditioned on external contexts (e.g., retrieved evidence), yet context use remains unreliable: models may overwrite an already-correct output (neutral regression) even when the context is non-informative. We formalize neutral regression as a do-no-harm requirement and quantify it by measuring accuracy drops on baseline-correct items under answer-consistent contexts. We propose No-Worse Context-Aware Decoding (NWCAD), a decode-time adapter built on a two-stream setup with a two-stage gate: it backs off to no-context decoding when the context is non-informative, and otherwise uses context-conditioned decoding with a CAD-style fallback under uncertainty. We evaluate NWCAD on benchmarks that separate do-no-harm reliability from context utilization (accuracy gains on genuinely helpful contexts). NWCAD prevents neutral regression on baseline-correct items while preserving strong context-driven accuracy on helpful contexts.
format Preprint
id arxiv_https___arxiv_org_abs_2604_16686
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle No-Worse Context-Aware Decoding: Preventing Neutral Regression in Context-Conditioned Generation
Tao, Yufei
Agrawal, Ameeta
Computation and Language
Artificial Intelligence
Large language models (LLMs) can answer questions and summarize documents when conditioned on external contexts (e.g., retrieved evidence), yet context use remains unreliable: models may overwrite an already-correct output (neutral regression) even when the context is non-informative. We formalize neutral regression as a do-no-harm requirement and quantify it by measuring accuracy drops on baseline-correct items under answer-consistent contexts. We propose No-Worse Context-Aware Decoding (NWCAD), a decode-time adapter built on a two-stream setup with a two-stage gate: it backs off to no-context decoding when the context is non-informative, and otherwise uses context-conditioned decoding with a CAD-style fallback under uncertainty. We evaluate NWCAD on benchmarks that separate do-no-harm reliability from context utilization (accuracy gains on genuinely helpful contexts). NWCAD prevents neutral regression on baseline-correct items while preserving strong context-driven accuracy on helpful contexts.
title No-Worse Context-Aware Decoding: Preventing Neutral Regression in Context-Conditioned Generation
topic Computation and Language
Artificial Intelligence
url https://arxiv.org/abs/2604.16686