在我國，隨著資本市場型態的改變，機構投資人持股比例有越來越高的趨勢，影響性亦日趨重大。由於機構投資人的投資策略往往是其他投資者關注的焦點，因此面對機構投資人持股與日俱增的情況，瞭解機構投資人的持股偏好與其對被投資公司的影響，對瞭解資本市場與公司治理皆有很大的助益。基於上述原因，本研究以國內上市上櫃公司作為研究對象，探討機構投資人是否會利用自身資訊優勢與風險承擔能力進行擇股，並進一步探討機構投資人在公司治理中的角色，分析其是否能顯著提昇公司價值。 研究發現，盈餘品質與機構投資人之持股呈顯著負相關，即盈餘品質越差， 機構投資人持股比例越高。本研究認為，此乃機構投資人身為精明的投資者，利用自身資訊優勢的利基，能洞悉公司盈餘品質不佳背後的真正原因，並挑選具成長潛力的公司進行投資之結果。此外，風險承擔與機構投資人之持股呈顯著負相關，即公司風險承擔能力越高，機構投資人持股比例越高。具有成長導向的風險承擔能使公司價值提升，而機構投資人在進行投資選股時，會選擇具有較高風險承擔能力的公司。於公司價值部分，本研究實證指出，若三大法人上一期持股越高，則下一期公司價值會有顯著改善。然若個別檢視三大法人之影響，則發現僅投信對公司價值有顯著提升，外資法人與自營商對公司價值雖有正向影響，但其結果並不顯著。總體而言，本研究認同機構投資人為積極投資者的持股角色，會積極介入公司營運管理，並改善公司價值，為股權的擁有者(owner)而非短視近利的短暫持有者(transient holder)。

sing a dataset record account-level trades and orders from Taiwan Futures Exchange, we examine whether the variations of risk taking follows the overconfidence bias for four types of traders, including individuals, foreign institutions, domestic institutions, and foreign institutional traders. Our findings show that when investors are individuals and domestic institutions, the variations of trading activities for overconfident investors are greater than others. However, the results are not significant for foreign institutions and foreign institutional traders. Therefore, we demonstrate that investors take more risk following overconfidence. / Using a dataset record account-level trades and orders from Taiwan Futures Exchange, we examine whether the variations of risk taking follows the overconfidence bias for four types of traders, including individuals, foreign institutions, domestic institutions, and foreign institutional traders. Our findings show that when investors are individuals and domestic institutions, the variations of trading activities for overconfident investors are greater than others. However, the results are not significant for foreign institutions and foreign institutional traders. Therefore, we demonstrate that investors take more risk following overconfidence.

我國在民國102年復徵證券交易所得稅，其本質屬於資本利得稅，本文欲探究資本利得稅對資產選擇之影響，再進一步將閉鎖效果納入資產選擇模型，討論課稅實現原則下，資本利得稅的稅率對資產選擇的影響。 本文假設兩項資產，分別為無風險性資產與風險性資產，發現在資本利得稅、資本損失可完全扣抵的情況下，政府擔任分散風險的角色，財富的風險性下跌，代表性個人增加風險性資產持有份額。納入閉鎖效果討論課徵資本利得稅下的資產選擇，設立兩期模型，代表性個人分配財富於無風險資產與風險性資產。若要代表性個人在第二期轉換投資組合，則代表性個人將要求新投資組合之報酬高於原資產之報酬加上處分原資產所產生之資本利得稅，而代表性個人可透過改變風險性資產持有比例調整新資產組合之報酬。研究發現，新投資組合的風險性資產持有比例受到原資產之資本利得稅率影響，原資產的稅率越高，則新投資組合的風險性資產持有比例越大，主因稅率越高，閉鎖效果的強度越強，因此若代表性個人要轉換資產的話，可透過增加風險性資產持有比例來增加新投資組合的預期報酬，亦表示代表性個人之風險承擔意願增加。

此論文包含三大部分。第一部分探討董監事暨重要職員責任保險(D&O保險)的需求因素與公司治理等企業特徵間的關係，配合2003-2007年台灣上市上櫃公司的資料，研究影響公司是否購買D&O保險、保險限額與保險費的決策因素。實證結果證明，大型公司較需要D&O保險保障，且公司的董監事與利害關係人間存在代理成本問題。本文亦發現董監事獨立性等公司治理因素，對D&O保險購買行為有顯著影響，再則，公司的成長性及經理人風險趨避態度，都會影響保險限額的決定。本文結論進一步顯示訴訟風險對保險限額的決定有正向顯著的影響，而財務風險對D&O保險需求亦有若干影響力。第二及第三部分則進一步探討董監事暨重要職員責任保險對公司的行為或策略是否有影響。實證結果顯示D&O保險確實會影響公司風險承擔策略及公司財報方法的穩健性。 / This thesis is comprised of three essays on directors’ and officers’ (D&O) liability insurance, one interesting but little explored research area. Based on an unbalanced panel data set of public Taiwanese corporations in years 2003-2007, the first essay investigates the relationship between directors’ and officers’ (D&O) insurance demand and firm characteristics, especially corporate governance. The results suggest that large firms are more likely to purchase D&O insurance, and that there exists agency cost between directors/officers and stakeholders. The findings indicate that corporate governance, such as board independence, has an important impact on D&O insurance demand. Besides, the results show that growth opportunity or managerial risk aversion can affect the D&O insurance coverage amount. The litigation risk also has a positive and significant impact on the D&O insurance amount, and bankruptcy risk weakly influences the D&O insurance demand. In the second essay, I provide evidence regarding corporate business strategy by investigating the relation between directors’ and officers’ (D&O) insurance and risk taking behavior. This essay tries to test (a) whether firms are more active to adopt risk-taking strategies when their directors and top managers are covered by D&O insurance coverage; (b) whether the quality of corporate governance has influence on firm’s risk-taking behavior; and (c) whether insurers can distinguish D&O insurance purchases decision driven by managerial risk-taking behavior and charge adequate premium rate for such behavior. The empirical evidence suggests that D&O insurance coverage has a positive impact on firm risk-taking behavior. In addition, the results indicate that board composition may remarkably influence corporate risk-taking behavior. The preliminary findings also show that insurers can assess the induced risk-taking behavior ex ante and charge adequate premiums rate accordingly. In the third essay, I investigate whether the legal liability coverage result in the propensity of less conservatism and aggressive managerial behavior/strategy. More specifically, this study tests managerial opportunism behavior by examining whether the purchase of D&O insurance coverage is associated with more aggressive financial reporting strategy (i.e., less accounting conservatism). The empirical evidence suggests that D&O liability insurance purchase decision is positively associated with accounting conservatism. That is, firms with insurance coverage tend to recognize bad news in a timely manner, i.e. more earning conservatism. However, there is no significant relation between accounting conservatism and D&O insurance amount. In addition, the evidence shows that firms with strong board structure recognize good news faster than those with weak governance structure.

工程契約係具特殊性質之承攬契約，而工程契約之開工、完工、驗收進程中，可能遭遇不同之風險事件，故本文先於第二章對工程契約之開工、完工、驗收及後續保固期間之意義及相關爭議為概略性之論述。 其次，於第三章先以一般承攬契約之風險分配為出發，就承攬契約之危險負擔、瑕疵擔保責任及定作人協力義務為概述，而在工程契約之風險分配原則上，採用「優勢風險承擔人原則」作為立論基礎，認為工程契約之風險應由對風險較具「預見能力」、「控制能力」及「規避能力」者承擔；進而就工程進程中不同階段可能遭遇之風險事件，建構可能之風險分配原則，並探究工程契約中常見「棄權條款」，包含工期展延、物價調整及權利行使期間等棄權條款，是否與合理之工程風險分配原則相符；另本文就工程保險契約制度為簡要之說明，並論述工程保險在工程實務中之地位，而將工程保險契約認定為工程契約分散風險之重要機制。 於第四章，特別針對國內論者甚少討論之「完工後驗收前」期間之實務爭議為判決整理及評析，而以本文建構之風險分配藍圖，對包含完工後驗收前之先行使用、減價驗收、部分驗收、試運轉及第三人侵權等爭議問題為分析。