E2A-Bench: Benchmarking Evidence-to-Action Reliability in Financial Chart Reasoning

Xiaoya Wang, Yutong Xu, Junjie Wang


Abstract
Can financial vision–language models (VLMs) turn chart evidence into reliable action recommendations? Existing hallucination evaluations are mostly claim-centric: they assess whether generated statements are supported, but not whether evidence remains traceable through rationale, confidence, and final action. We introduce E2A-Bench, a 969-query benchmark for financial chart reasoning, constructed from 323 HS300 constituents under three input modalities with deterministic OHLCV-derived evidence anchors. E2A-Bench evaluates grounding, reasoning–action consistency, evidence–confidence calibration, and directional coverage through UCR, RCI, ECI, and NDR, where NDR measures coverage-aware evidence-to-action reliability rather than realized trading performance. Evaluating 20 VLMs reveals three failures hidden by scalar hallucination scores: the lowest-UCR model ranks near the bottom by NDR due to only 6.4% directional coverage; oracle-aided verification reduces unsupported claims but can collapse coverage; and financial fine-tuning amplifies the BUY:SELL ratio by 4.21–4.68× across strict base–fine-tuned pairs. These results show that financial VLM evaluation should trace the full evidence-to-action chain rather than rely on a single hallucination score. Code and data: https://github.com/wanng-ide/E2A-Bench .
Anthology ID:
2026.findings-emnlp.450
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
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SIGDAT
Publisher:
Association for Computational Linguistics
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Pages:
9448–9465
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URL:
https://aclanthology.org/2026.findings-emnlp.450/
DOI:
Bibkey:
Cite (ACL):
Xiaoya Wang, Yutong Xu, and Junjie Wang. 2026. E2A-Bench: Benchmarking Evidence-to-Action Reliability in Financial Chart Reasoning. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 9448–9465, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
E2A-Bench: Benchmarking Evidence-to-Action Reliability in Financial Chart Reasoning (Wang et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.450.pdf