內部治理能否限制過度自信的CEO帶來之負面影響

Abstract

本研究探討企業內部治理機制是否能有效緩解過度自信CEO對公司所造成的負面影響。本文選取2003年至2023年間美國上市公司為樣本，建立CEO過度自信指標，並使用獨立董事比率、高階主管預期服務年限與高階主管監督力道作為內部治理指標，透過OLS迴歸模型驗證三項假說。實證結果顯示，獨立董事比率能有效抑制過度投資行為並降低投資－現金流敏感性，高階主管監督力道則能減緩過度自信CEO對公司價值與營運表現的損害，亦能降低投資－現金流敏感性。相對而言，高階主管預期服務年限未能有效達成預期效果。研究結果提供了企業在加強內部治理時的重要參考依據，亦對過度自信與公司治理領域之實證文獻作出貢獻。

This study investigates whether corporate internal governance mechanisms can effectively mitigate the negative impacts caused by overconfident CEOs. Using a sample of U.S. listed companies from 2003 to 2023, we construct an overconfidence measure based on CEO option holdings and employ three internal governance indicators: the proportion of independent directors, the expected tenure of top executives, and the relative power of top executives. We apply OLS regression models to test three hypotheses. Empirical results show that a higher proportion of independent directors effectively restrains overinvestment behavior and reduces investment–cash flow sensitivity, while stronger top executive power mitigates the adverse effects of overconfident CEOs on firm value and performance, as well as lowers investment–cash flow sensitivity. Conversely, the expected tenure of top executives does not show the expected moderating effects. Our findings provide important practical implications for strengthening internal governance and contribute to the literature on CEO overconfidence and corporate governance.