營建業轉投資基礎建設案對公司股價表現之影響-以大陸工程公司為例

Abstract

近年來營建業景氣低迷，營建業者試圖轉投資以求發展，積極以民間參與公共建設的方式參與基礎建設投資，並成立特許公司，如大陸工程與台灣高鐵的關係。然而BOT專案風險範圍廣大而較難控制，特許公司好壞消息的發佈對營建業本身股價將造成影響。 本研究採事件研究法，先將選出的樣本以好壞分類；接著運用市場模式建構本研究模型，對於事件期間的超常報酬率進行統計檢定，分析資訊內涵對於股價的影響，同時探討其情報效果，以分析當台灣高鐵有重大訊息發布時，主要股東「大陸工程公司」股價之異常現象。 研究結果顯示，在好消息宣告期間，大陸工程之超常報酬率為正值，並在宣告日次日呈現統計上顯著大於零，可確定大陸工程公司股價波動與高鐵重大訊息有關連。由於本研究尚以營建類股指數取代大盤指數做為市場指標，以釐清超常報酬率是否來自重大訊息的影響，或者是營建類股的特殊性，利多樣本部分雖然有負的超常報酬率，卻未達統計上的顯著，因此無法斷言不利的訊息是否對大陸工程股價有負面影響。

The constructers in Taiwan reinvested in other industries due to the depression of economy in the past years. Some of them took part in infrastructures aggressively through the Build-Operate-Transfer model and formed the concession companies, for example, CEC(Continental Engineering Corporation) and THSRC(Taiwan High Speed Rail Corporation). However the risks of BOT projects are various and complicated, the news about projects may cause some impacts on stock performance. The study uses CEC as empirical case via event study, ordinary least squares market model, and statistic test method. The main issues include how does abnormal return in event period? Is it significant？ The finding is that during the good news event window, CEC stock price positively abnormal changes and significant at the day afer event day. Thus, sure of CEC stock performance is related to good news of THSRC. In this study, using Construction index instead of Market Summary as market index to figure out how the negative abnormal return happened. Just because of the bad news or the particularity from construction？However, negative AR is not significant during the event window. From this case, cannot sure CEC stock performance is related to bad news of THSRC.