FinLFQA: Evaluating Attributed Text Generation of LLMs in Financial Long-Form Question Answering
Yitao Long, Tiansheng Hu, Yilun Zhao, Arman Cohan, Chen Zhao
TL;DR
FinLFQA tackles hallucination in financial long-form QA by introducing a multi-faceted attribution benchmark and an automated, fine-grained evaluation framework. It formalizes the task with clause-level statements carrying evidence, intermediate Python reasoning, and domain-knowledge links, evaluated across eight LLMs through three generation paradigms. The results show that end-to-end generation matches post-hoc performance, iterative refinement yields limited gains without external feedback, and domain-specific guidance significantly enhances outcomes. The benchmark demonstrates the importance of precise numerical reasoning and knowledge grounding for finance, with GPT-4o achieving the strongest overall performance but open-source models approaching parity in several dimensions. Limitations include a two-company setup and a call for broader data to further stress-test attribution in high-stakes financial QA.
Abstract
Large Language Models (LLMs) frequently hallucinate to long-form questions, producing plausible yet factually incorrect answers. A common mitigation strategy is to provide attribution to LLM outputs. However, existing benchmarks primarily focus on simple attribution that retrieves supporting textual evidence as references. We argue that in real-world scenarios such as financial applications, attribution goes beyond reference retrieval. We introduce FinLFQA, a benchmark designed to evaluate the ability of LLMs to generate long-form answers to complex financial questions with reliable and nuanced attributions. FinLFQA evaluates three critical aspects of attribution through human annotations: (1) supporting evidence extracted from financial reports, (2) intermediate numerical reasoning steps, and (3) domain-specific financial knowledge that informs the reasoning process. We further provide an automatic evaluation framework covering both answer quality and attribution quality. Through extensive experiments on eight LLMs across multiple attribution-generation paradigms, we find that fine-grained metrics are important to distinguish model capabilities, that end-to-end generation achieves comparable performance to post-hoc approaches, and that iterative refinement only helps when guided by external feedback.
