Chance-Constrained Inference for Hallucination Risk Control in Large Language Models
- URL: http://arxiv.org/abs/2602.01637v1
- Date: Mon, 02 Feb 2026 04:51:47 GMT
- Title: Chance-Constrained Inference for Hallucination Risk Control in Large Language Models
- Authors: Sreenivasan Mohandas,
- Abstract summary: Large language models generate fluent but invalid responses, including factual hallucinations.<n>We formulate inference as a deployment-time risk control problem.<n>We show that confidence-based selective prediction does not, in general, imply probabilistic risk guarantees.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Large language models generate outputs stochastically and may produce fluent but invalid responses, including factual hallucinations. Existing mitigation strategies reduce average error rates but do not provide explicit control over the \emph{frequency} of such failures under repeated use. We formulate inference as a deployment-time risk control problem and introduce \emph{chance-constrained inference}, which directly bounds the probability of hallucinations among accepted generations. Hallucinations are modeled as stochastic constraint violations, and we show that confidence-based selective prediction does not, in general, imply probabilistic risk guarantees. To enforce chance constraints efficiently, we propose a sequential, anytime-valid inference procedure that adaptively certifies feasibility or infeasibility using finite samples, avoiding conservative fixed-sample bounds. Experiments on questions inspired by NaturalQuestions and controlled multi-hop question answering demonstrate reliable risk control, early detection of intrinsically infeasible inputs, and safe composition under repeated use, while confidence-based baselines fail to provide consistent guarantees.
Related papers
- Probabilistic Guarantees for Reducing Contextual Hallucinations in LLMs [0.0]
Large language models (LLMs) frequently produce contextual hallucinations, where generated content contradicts or ignores information explicitly stated in the prompt.<n>We introduce a model-agnostic framework that provides explicit probabilistic guarantees for reducing hallucinations in this setting.<n>We prove that the probability that the judged pipeline fails decays at a rate determined by the judge's true and false-positive probabilities.
arXiv Detail & Related papers (2026-01-02T10:52:33Z) - HaluNet: Multi-Granular Uncertainty Modeling for Efficient Hallucination Detection in LLM Question Answering [12.183015986299438]
We present textbfHaluNet, a lightweight and trainable neural framework that integrates multi granular token level uncertainties.<n> Experiments on SQuAD, TriviaQA, and Natural Questions show that HaluNet delivers strong detection performance and favorable computational efficiency.
arXiv Detail & Related papers (2025-12-31T02:03:10Z) - LEC: Linear Expectation Constraints for False-Discovery Control in Selective Prediction and Routing Systems [95.35293543918762]
Large language models (LLMs) often generate unreliable answers, while uncertainty methods fail to fully distinguish correct from incorrect predictions.<n>We address this issue through the lens of false discovery rate (FDR) control, ensuring that among all accepted predictions, the proportion of errors does not exceed a target risk level.<n>We propose LEC, which reinterprets selective prediction as a constrained decision problem by enforcing a Linear Expectation Constraint.
arXiv Detail & Related papers (2025-12-01T11:27:09Z) - Trusted Uncertainty in Large Language Models: A Unified Framework for Confidence Calibration and Risk-Controlled Refusal [31.458406135473805]
We present UniCR, a unified framework that turns heterogeneous uncertainty evidence into a calibrated probability of correctness.<n>UniCR learns a lightweight calibration head with temperature scaling and proper scoring.<n>Experiments on short-form QA, code generation with execution tests, and retrieval-augmented long-form QA show consistent improvements in calibration metrics.
arXiv Detail & Related papers (2025-09-01T13:14:58Z) - Semantic Energy: Detecting LLM Hallucination Beyond Entropy [106.92072182161712]
Large Language Models (LLMs) are being increasingly deployed in real-world applications, but they remain susceptible to hallucinations.<n>Uncertainty estimation is a feasible approach to detect such hallucinations.<n>We introduce Semantic Energy, a novel uncertainty estimation framework.
arXiv Detail & Related papers (2025-08-20T07:33:50Z) - COIN: Uncertainty-Guarding Selective Question Answering for Foundation Models with Provable Risk Guarantees [51.5976496056012]
COIN is an uncertainty-guarding selection framework that calibrates statistically valid thresholds to filter a single generated answer per question.<n>COIN estimates the empirical error rate on a calibration set and applies confidence interval methods to establish a high-probability upper bound on the true error rate.<n>We demonstrate COIN's robustness in risk control, strong test-time power in retaining admissible answers, and predictive efficiency under limited calibration data.
arXiv Detail & Related papers (2025-06-25T07:04:49Z) - Constrained Discrete Diffusion [61.81569616239755]
This paper introduces Constrained Discrete Diffusion (CDD), a novel integration of differentiable constraint optimization within the diffusion process.<n>CDD directly imposes constraints into the discrete diffusion sampling process, resulting in a training-free and effective approach.
arXiv Detail & Related papers (2025-03-12T19:48:12Z) - To Believe or Not to Believe Your LLM [51.2579827761899]
We explore uncertainty quantification in large language models (LLMs)
We derive an information-theoretic metric that allows to reliably detect when only epistemic uncertainty is large.
We conduct a series of experiments which demonstrate the advantage of our formulation.
arXiv Detail & Related papers (2024-06-04T17:58:18Z) - Mitigating LLM Hallucinations via Conformal Abstention [70.83870602967625]
We develop a principled procedure for determining when a large language model should abstain from responding in a general domain.
We leverage conformal prediction techniques to develop an abstention procedure that benefits from rigorous theoretical guarantees on the hallucination rate (error rate)
Experimentally, our resulting conformal abstention method reliably bounds the hallucination rate on various closed-book, open-domain generative question answering datasets.
arXiv Detail & Related papers (2024-04-04T11:32:03Z) - Non-Convex Robust Hypothesis Testing using Sinkhorn Uncertainty Sets [18.46110328123008]
We present a new framework to address the non-robust hypothesis testing problem.
The goal is to seek the optimal detector that minimizes the maximum numerical risk.
arXiv Detail & Related papers (2024-03-21T20:29:43Z) - Probabilities Are Not Enough: Formal Controller Synthesis for Stochastic
Dynamical Models with Epistemic Uncertainty [68.00748155945047]
Capturing uncertainty in models of complex dynamical systems is crucial to designing safe controllers.
Several approaches use formal abstractions to synthesize policies that satisfy temporal specifications related to safety and reachability.
Our contribution is a novel abstraction-based controller method for continuous-state models with noise, uncertain parameters, and external disturbances.
arXiv Detail & Related papers (2022-10-12T07:57:03Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.