CAST: Achieving Stable LLM-based Text Analysis for Data Analytics

Jinxiang Xie, Zihao Li, Wei He, Rui Ding, Shi Han, Dongmei Zhang


Abstract
Text analysis of tabular data relies on two core operations: summarization for corpus-level theme extraction and tagging for row-level labeling. A critical limitation of employing large language models (LLMs) for these tasks is their inability to meet the high standards of output stability demanded by data analytics. To address this challenge, we introduce CAST (Consistency via Algorithmic Prompting and Stable Thinking), a framework that enhances output stability by constraining the model’s latent reasoning trajectory. CAST combines (i) Algorithmic Prompting to impose a procedural scaffold over valid reasoning transitions and (ii) Thinking-before-Speaking to enforce explicit intermediate commitments before final generation. To measure progress, we introduce CAST-S and CAST-T, stability metrics for bulleted summarization and tagging, and validate their alignment with human judgments. Experiments across publicly available benchmarks on multiple LLM backbones show that CAST consistently achieves the best stability among all baselines, improving Stability Score by up to 16.2%, while maintaining or improving output quality.
Anthology ID:
2026.findings-acl.113
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
2401–2420
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.113/
DOI:
Bibkey:
Cite (ACL):
Jinxiang Xie, Zihao Li, Wei He, Rui Ding, Shi Han, and Dongmei Zhang. 2026. CAST: Achieving Stable LLM-based Text Analysis for Data Analytics. In Findings of the Association for Computational Linguistics: ACL 2026, pages 2401–2420, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
CAST: Achieving Stable LLM-based Text Analysis for Data Analytics (Xie et al., Findings 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.113.pdf
Checklist:
 2026.findings-acl.113.checklist.pdf