最近許多財務的實證研究發現股價對公司某些決策長期異常反應,這些結果隱含股 價對公開資訊反應不足或過度反應,其發現顯然拒絕效率市場假說。因此,本研究同時 探討台灣上市(櫃)公司多種管理決策後之長期績效,不同於其他研究者只注意單一事 件,本研究包括新上市(櫃)、上櫃轉上市、現金增資、債券發行、公開市場買回庫藏股 以及購併等事件。此外,本研究也將提供在各種異常績效衡量方法下之結果。最後,我 們進一步評估現存之理論模式,以便幫助解釋我們的結果。 Recent empirical studies in finance document long-run abnormal price reactions subsequent to numerous corporate decisions. Since these results imply that stock prices under-react or over-react to publicly available information, they appear to be at odds the efficient markets hypothesis. Therefore, this study is to explore the long-run performance following major managerial decisions in Taiwan. Unlike other researchers, which look only at one event, we include initial public offerings, exchage listings, seasoned equity offerings, debt offerings, open market share repurchases, mergers and acquisitions. In addition, we provide thorough evidence on various methods of measuring abnormal performance. Finally, to help explain our results, we are to evaluate existing theoretical models.