本研究以2004年至2009年之高科技產業為研究對象，探討台灣企業是否會投機地使用裁決權去低估選擇權價值。實證結果發現高科技產業平均低估每一權員工認股選擇權之公平價值NT$1.76元。此外，公司操縱選擇權評價模型參數包括縮短存續期間參數和減少股價波動率參數使其公平價值低估。
　　進一步探討公司裁決性選擇權價值之誘因以及公司治理機制對裁決性選擇權價值之影響。實證結果發現淨值報酬率和已實現股價波動率與裁決性選擇權價值呈負相關，顯示當公司之淨值報酬率和已實現股價波動率越大時，越會誘發公司低估選擇權價值。但隨著公司治理機制越好，將會弱化公司操縱選擇權評價模型之誘因，並且改善公司的裁決性員工認股選擇權價值。

　　This study investigates whether firms in Taiwan exercise discretion over employee stock option (ESO) valuation-model inputs to understate employee stock option values. Using 302 high-tech firms in Taiwan from 2004 to 2009, the empirical results suggests the difference between per option value using reported inputs and that using expected inputs is NT$-1.76. It means that firms use discretion to underreport employee stock option values. Further, the results find that managers the understatement of ESO values is mainly attributable to discretion over option life and stock return volatility.
　　The study also explores the consequences of such discretion and the relationship between corporate governance and discretionary ESO value. The empirical results show that ROE and realized stock return volatility negatively affect discretionary ESO value, indicating that firms with larger ROE and realized stock return volatility underreport ESO values. More importantly, strong corporate governance can weaken incentives to improve the magnitude of discretionary ESO value.

英文
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