本文主要對中國大陸企業海內外併購事件宣告效果進行分析，探究被併企業所在國之發展程度及文化距離對股價之異常報酬率的影響。本文選取2008年1月1日至2015年12月31日中國大陸在上海和深圳交易所上市的公司發生的併購事件為樣本，運用事件研究法進行分析。根據T檢定及多元迴歸結果顯示，通過併購實現外部擴張對於中國大陸上市公司來說是一種合理有效的方式，從總體上看併購事件給企業帶來正的累積異常報酬率。同時被併企業所在國在已開發國家會給主併公司股東帶來更多的異常報酬。本文還針對海外併購事件進行迴歸分析，發現被併企業所在國與中國大陸的文化距離越遠，主併企業的短期併購績效越好。

自1990年代中期，隨著環保、消費者權利、童工…等這些議題被廣泛檢討，越來越多人同意各別公司與整個社會是價值共享且相互依存的，若要達到共存共榮的理想，則公司必定要將社會責任融入其自身追求競爭力和商業策略的核心架構中。企業社會責任(Corporate Social Responsibility)並無公認標準，但一般泛指企業除了追求股東的利益極大化外，還必須兼顧員工、顧客、供應商、合作夥伴、社區團體、環境…等。 道瓊永續性指數(Dow Jones Sustainability Index)為現今資本市場衡量企業社會責任的標竿指數，而企業名列在被大眾認可的永續性指數上，就是企業可以傳達給利益相關者(stakeholders)，表明他們注重企業社會責任的訊號之一。藉由研究企業被涵蓋在聲譽卓著的永續性指數之內是否能為股東創造價值，本論文將探討企業永續發展和企業價值之間的複雜關係。 本研究利用傾向分數配對法(Propensity Score Matching)，降低進入與退出道瓊永續性指數這兩組公司間的異質性，以求得出的結果較不受公司規模、財務槓桿、產業等外在其他因素干擾。將2002至2009年間的樣本數配對後，以道瓊永續性指數作為企業社會責任之代理變數，以累積異常報酬率(Cumulative abnormal return)代表為股東創造之財富，我們追蹤資本市場對於企業進入和退出道瓊永續性指數的反應，來探討股東是否認同公司參與企業社會責任是創造價值之行為。 本研究結果顯示如下: 第一、當企業被加入道瓊永續性指數時，該企業之股東將獲得正向且顯著性的累積異常報酬率，這代表名列著名的的永續性指數是一個股東認可，且企業應追尋的目標。第二、當企業被道瓊永續性指數剔除時，該企業之股東將獲得負向但不顯著的累積異常報酬率。因此我們至少可以推論，從事企業社會責任活動，並不會破壞企業整體之價值。 / Corporate social responsibility (CSR) gradually becomes an important corporate strategy to every company in the worldwide economy. The social performance of a firm can shape the images to key stakeholders, no matter they are employees, suppliers, customers or investors, and influence decision making and relationships with the firm in the later stage. While corporations are busy engaging and enhancing CSR practices, there are few established empirical research on CSR effects and relevance in the capital markets. Hence, my thesis explores the relationship between corporate sustainability and firm value by asking whether membership on a recognized sustainability index is value generating. As stakeholders are urging that firms demonstrate their commitment to sustainability, one signal that companies can send to stakeholders to indicate that they are sustainable is membership on a recognized sustainability index. My research investigates this issue by tracing the market reaction to corporate entries and exits from Dow Jones Sustainability Index, recognized as a CSR benchmark, between 2002 and 2009. Instead of using regression models, I employ a propensity score matching (PSM) pairs design to overcome heterogeneity between different firms. My thesis highlights two main findings: a significant share price rising trend in cumulative abnormal returns (CAR) of the samples under the addition situation, suggesting that inclusion on the Dow Jones Sustainability Index (DJSI) is a goal that firms should pursue. Another is an insignificant negative stock market reaction while firms are removed from the DJSI, and I can draw from the results that, at the very least, adopting CSR doesn’t deteriorate the value of the firms. Our results suggest that the benefits of being included on the DJSI outweigh or equal to the costs associated with applying a membership on DJSI.

為了落實賦稅公平、實現社會正義，財政部推出證券交易所得課稅方案，希望能達到此目標。為探討資本市場對證券交易所得課稅方案演變的預期，本論文利用事件研究法探討在證券交易所得稅復徵消息公布至通過三讀立法期間之相關事件，對上、市櫃公司之股票累積異常報酬率之影響，並採用迴歸模型探討該股票累積異常報酬率與公司特性之關聯性。 本論文之研究結果發現： 1.在證券交易所得稅相關消息公布之事件日，上市櫃公司均產生顯著之股票累積異常報酬率。 2.課徵證券交易所得稅相關消息公布之事件期間，股票累積異常報酬率與公司特性關聯性之迴歸結果顯示：公司規模較大之公司，其公司股票累積異常報酬率較高；負債比率較高、公司成長性較高之公司，其公司股票累積異常報酬率較低。 / In order to implement the principle of fair taxation, Ministry of Finance, R.O.C. address that gains from securities transactions shall be subject to income tax. The amendment is expected to have impacts on stock market returns of all companies. Using event study methods, this study examines the stock market reactions to the announcements of the legislature policy and explores the relation between the stock cumulative abnormal returns (CAR) of the amendment and firm characteristics. This study finds that the stock market reacts negatively (positively) when the news of the amendment are released (revised). The regression results indicate that CARs are negatively related with debt ratios and corporate growth; positively related with corporate size.