本論文包含兩篇實證研究，探討網路安全風險與共同機構持股對企業勞動力投資效率之影響。 第一篇研究檢視網路安全風險與勞動力投資效率之間的關聯。本文根據資源基礎理論及協作文化相關文獻，主張網路安全風險可能同時對人力資本管理形成約束與激勵。利用企業層級的文字分析法量化網路風險指標，並結合2009年至2018年間美國上市公司資料，研究結果顯示網路安全風險與勞動力投資效率呈顯著正相關。此正向關係在資訊科技投資較高、自動化潛力較強、技術勞工比例較高，以及具備協作文化的企業中更加明顯。此發現顯示，雖然網路風險常被視為干擾來源，但亦可能促使企業進行內部轉型，提升人力資源配置效率。 第二篇研究分析共同機構持股對勞動力投資效率的影響。雖然共同持股有助於投資組合公司間的協調，但也可能削弱公司治理並降低經理人自律。實證結果顯示，共同持股程度越高的企業，其勞動力投資效率越低。進一步分析指出，這種低效率並非來自於過度招聘或用人不足，而主要是由於未能及時裁減冗員，即所謂的裁員不足。此行為反映出在外部競爭與內部監督壓力降低的情況下，企業管理階層的調整反應能力下降，符合「安逸生活」假說的預期。這種負面影響在市場競爭程度較低與財務揭露品質較弱的企業中更為明顯。 ;This thesis presents two empirical studies that investigate how cybersecurity risk and common institutional ownership affect labor investment efficiency. The first analysis explores how cybersecurity risk is associated with a firm’s efficiency in labor investment decisions. Drawing on resource-based theory and literature on collaborative culture, it argues that cybersecurity risk can act both as a constraint and a catalyst for human capital management. By applying a text-based indicator of firm-level cybersecurity exposure and utilizing panel data for U.S.-listed firms from 2009 to 2018, this study reveals a statistically significant positive relationship between cybersecurity risk and labor investment efficiency. This effect is especially strong in firms with higher IT investment, greater automation potential, more skilled labor, and stronger collaborative cultures. The results suggest that cybersecurity risk, though often viewed as disruptive, may drive internal transformation and more efficient workforce allocation. The second analysis examines how common institutional ownership affects labor investment efficiency. While such ownership may improve coordination among portfolio firms, it can also weaken governance and reduce managerial discipline. Using data on U.S. public firms, the study finds that higher common ownership is associated with lower labor investment efficiency, primarily due to under-firing—firms retaining excess labor when reductions are warranted. This reflects diminished managerial responsiveness under weaker external and internal pressure, aligning with the quiet life hypothesis. The negative effect is more evident in less competitive industries and firms with lower financial reporting quality.
