TempPerturb-Eval: On the Joint Effects of Internal Temperature and External Perturbations in RAG Robustness

Yongxin Zhou, Philippe Mulhem, Didier Schwab


Abstract
The evaluation of Retrieval-Augmented Generation (RAG) systems typically examines retrieval quality and generation parameters like temperature in isolation, overlooking their interaction. This work presents a systematic investigation of how text perturbations (simulating noisy retrieval) interact with temperature settings across multiple LLM runs. We propose a comprehensive RAG Perturbation-Temperature Analysis Framework that subjects retrieved documents to three distinct perturbation types across varying temperature settings. Through extensive experiments on HotpotQA with both open-source and proprietary LLMs, we demonstrate that performance degradation follows distinct patterns: high-temperature settings consistently amplify vulnerability to perturbations, while certain perturbation types exhibit non-linear sensitivity across the temperature range. Our work yields three key contributions: (1) a diagnostic benchmark for assessing RAG robustness, (2) an analytical framework for quantifying perturbation-temperature interactions, and (3) practical guidelines for model selection and parameter tuning under noisy retrieval conditions.
Anthology ID:
2026.lrec-main.9
Volume:
Proceedings of the Fifteenth Language Resources and Evaluation Conference
Month:
May
Year:
2026
Address:
Palma de Mallorca, Spain
Editors:
Stelios Piperidis, Núria Bel, Henk van den Heuvel, Nancy Ide, Simon Krek, Antonio Toral
Venue:
LREC
SIG:
Publisher:
ELRA Language Resource Association
Note:
Pages:
117–127
Language:
URL:
https://preview.aclanthology.org/ingest-lrec/2026.lrec-main.9/
DOI:
Bibkey:
Cite (ACL):
Yongxin Zhou, Philippe Mulhem, and Didier Schwab. 2026. TempPerturb-Eval: On the Joint Effects of Internal Temperature and External Perturbations in RAG Robustness. International Conference on Language Resources and Evaluation, main:117–127.
Cite (Informal):
TempPerturb-Eval: On the Joint Effects of Internal Temperature and External Perturbations in RAG Robustness (Zhou et al., LREC 2026)
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PDF:
https://preview.aclanthology.org/ingest-lrec/2026.lrec-main.9.pdf