ESG表現對審計定價影響之實證研究：兼論資訊不對稱與營運效率之中介機制

An Empirical Study on the Impact of ESG Performance on Audit Pricing: The Mediating Roles of Information Asymmetry and Operational Efficiency

本研究旨在探討企業環境、社會與公司治理(ESG)表現對審計公費之影響，並進一步檢驗資訊不對稱與營運效率是否構成中介機制，同時分析審計品質（Big4會計師事務所）是否帶來異質性效果。以臺灣2018至2023年上市公司為樣本，結合TEJESG評分與公開財報資料，採用固定效果模型、多元迴歸、Baron與Kenny中介效果分析、Bootstrap檢定與兩階段最小平方法(2SLS)進行實證檢驗。實證結果顯示，企業ESG表現與審計公費之間具有顯著正向關聯，顯示會計師可能將ESG資訊揭露與風險控管納入報價考量。進一步分析發現，資訊不對稱為此關係重要中介機制，而營運效率(OPM)則未具顯著中介效果。異質性檢驗亦指出，在四大事務所查核樣本中，ESG對審計費用影響更為顯著，顯示審計品質調節效果。2SLS分析結果亦驗證ESG為具內生性之變數，強化研究模型之因果解釋力。本研究填補ESG表現與審計定價間傳導機制之文獻空缺，並提出資訊不對稱為關鍵橋樑，對監理機關、企業治理與會計師查核實務提供理論與政策建議。本研究亦指出，ESG表現對審計公費效應需建基於資訊透明度與查核品質之提升，方能有效發揮其市場功能。

This study investigates the relationship between corporate Environmental, Social, and Governance (ESG) performance and audit fees, with a particular focus on the mediating roles of information asymmetry and operating efficiency, and the moderating effect of audit quality (proxied by Big 4 audit firms). Using panel data of publicly listed firms in Taiwan from 2018 to 2023, the study employs fixed-effects regression models, Baron and Kenny's mediation analysis, non-parametric bootstrap testing, and two-stage least squares (2SLS) to address potential endogeneity. Empirical results show a significantly positive association between ESG scores and audit fees, indicating that auditors may allocate more resources and risk premiums when evaluating firms with stronger ESG disclosures. Mediation analysis reveals that information asymmetry, measured by the kv_index (price range ratio), plays a significant mediating role, while operating profit margin (OPM) does not exhibit a significant indirect effect. Heterogeneity analysis further confirms that the ESG–audit fee relationship is stronger among firms audited by Big 4 firms, suggesting heightened sensitivity to ESG-related risks among higher-quality auditors. Additionally, 2SLS analysis using lagged ESG scores as instruments confirms the robustness of the results and the presence of endogeneity. This study contributes to the auditing and ESG literature by clarifying the cost implications of ESG performance through the lens of information asymmetry and audit quality. It provides practical implications for regulators, firms, and auditors regarding ESG assurance, disclosure transparency, and audit pricing strategies in sustainability reporting environments.