資訊不確定性的程度會影響債權人與股東對投資所要求的風險貼水。市場對於CEO能力的不確定性是影響公司資訊不確定性的主要原因之一。根據Pan et al. (2015)，CEO工作年間影響市場認知CEO能力的速度，故本研究著重在CEO工作年間的影響。實證結果發現，隨著CEO上任期間越長，資訊不確定性越低，且資訊不確定下降幅度於前3年最為明顯，而後緩慢下降；但對於上任期間較長的CEO，其就任期間對資訊不確定性的影響較小。

A firm’s degree of information uncertainty affects the risk premiums of both its debt and equity investors. The information of a firm’s CEO ability is one of the main sources affecting firm uncertainty. According to Pan et al. (2015), CEO tenure affects market learning in CEO ability. The main purpose of this study therefore focuses on the effect of CEO tenure on firm’s information uncertainty. The results of the empirical show that the degree of a firm’s information uncertainty increases when a new CEO takeover. The longer the CEO tenure, the less the degree of information uncertainty. Additionally, significant decline of information uncertainty happens within the first 3 years.

口試委員會審定書 #
誌謝 i
中文摘要 ii
ABSTRACT iii
目錄 iv
圖表目錄 v
第一章 導論 1
第二章 模型概述與回顧 4
第三章 研究假說 6
第四章 研究樣本與研究方法 8
第一節 主要變數 8
第二節 應變數 9
第一項 應記帳品質 (Accrual Quality) 9
第二項 分析員預測價值分散度 (DISP) 10
第三節 控制變數 10
第一項 公司規模 (Firm Size) 10
第二項 股權波動度(Equity Volatility) 10
第三項 公司財務槓桿比率(Leverage) 10
第四節 敘述統計 11
第五節 研究方法 11
第五章 實證結果與分析 13
第六章 結論 16
第七章 參考文獻 17

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8. Murphy, Kevin J. and Jerold L. Zimmerman, 1993, “Financial Performance Surrounding CEO Turnover,” Journal of Accounting and Economics, 16, 273-31 
9. Mansi, Satter, William Maxwell and Darius Miller, 2011, “Analyst Forecast Characteristics and the Cost of Debt,” Review of Accounting Studies, 16, 116-142. 
10. Pastor, Lubos and Pietro Veronesi, 2009, “Learning in Financial Markets,” Annual Review of Financial Economics, 1,361-381. 
11. Pan, Yihui, Tracy Yue, Wang and Michael S. Weisbach, 2015, “Learning About CEO Ability and Stock Return Volatility,” Review of Financial Studies, 28(6), 1623-1666. 
12. Pan, Yihui, Tracy Yue, Wang and Michael S. Weisbach, 2016a, “CEO Investment Cycles,” Review of Financial Studies, 29, 2955-2999. 
13. Weisbach, Michael S., 1995, “CEO Turnover and the Firm’s Investment Decisions,” Journal of Financial Economics, 37, 155-188.5. 
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