Order Matters in Hallucination: Reasoning Order as Benchmark and Reflexive Prompting for Large-Language-Models
Zikai Xie
TL;DR
This work investigates hallucinations in large language models and the impact of the order in which reasoning and answers are produced. It introduces Reasoning Order as Benchmark to quantify model consistency across answer-first and logic-first prompts, and Reflexive Prompting, a two-step prompting strategy that leverages both outputs to improve reliability without retraining. Empirical results across multiple datasets and models show that reflexive prompting often yields higher accuracy and that consistency metrics correlate with performance, supporting the method as a practical diagnostic and improvement tool. The findings offer a cost-efficient approach to enhance LLM reliability in high-stakes settings and suggest directions for future decoder-level or inference-time enhancements.
Abstract
Large language models (LLMs) have generated significant attention since their inception, finding applications across various academic and industrial domains. However, these models often suffer from the "hallucination problem", where outputs, though grammatically and logically coherent, lack factual accuracy or are entirely fabricated. A particularly troubling issue discovered and widely discussed recently is the numerical comparison error where multiple LLMs incorrectly infer that "9.11$>$9.9". We discovered that the order in which LLMs generate answers and reasoning impacts their consistency. Specifically, results vary significantly when an LLM generates an answer first and then provides the reasoning versus generating the reasoning process first and then the conclusion. Inspired by this, we propose a new benchmark method for assessing LLM consistency: comparing responses generated through these two different approaches. This benchmark effectively identifies instances where LLMs fabricate answers and subsequently generate justifications. Furthermore, we introduce a novel and straightforward prompt strategy designed to mitigate this issue. Experimental results demonstrate that this strategy improves performance across various LLMs compared to direct questioning. This work not only sheds light on a critical flaw in LLMs but also offers a practical solution to enhance their reliability.
