在初次上櫃之前，企業與投資者存在資訊不對稱問題，這時媒體扮演極為重要的資訊傳遞角色。然而，資訊傳遞是否有效一直是被廣泛討論的議題。本文以報導次數作為衡量媒體報導強度的指標，並運用2007年至2013年從興櫃市場轉至櫃買市場的個股，透過一年期長期績效驗證媒體在企業上櫃前的資訊傳遞是否有效。本文發現報導次數與長期績效的關聯性為負相關，而短期報酬與長期績效亦呈現負相關，隱含在上櫃前媒體報導會過度推升股價，促使個股股價會偏離基本價值。然而，欲強化報導次數與長期績效的關聯性，運用Amihud反流動性比率證實個股是因為嚴重的資訊不對稱因而造成報導次數與長期績效的負向關係。;Information asymmetry problem shows between issuing companies and investors before an enterprise lists in the over-the-counter market. However, it is widely discussed by researchers that whether information is disseminated efficiently or not. This paper takes coverage times as the strength of media coverage, and selects stocks which was registering on over-the-counter market from emerging stock market between 2007 and 2013, then uses one year long term return to confirm whether information can be conveyed by media effectively. This paper finds that both of the relation between coverage times and long term performance as well as the relation between short term return and long term performance were negative, it implies that media coverage will rise stock price sharply when stock was preparing to offer initial public offering (IPO) to public, then inducing stock price deviated far from fundamental value. Nevertheless, in order to verify relation between coverage times and long term performance, this paper use Amihud illiquidity ratio to affirm negative relation is due to serious information asymmetry.
