公司宣告產品召回對自身與其競爭者之長短期股價報酬之影響

Abstract

本研究旨在探討臺灣上市櫃公司宣告產品召回事件，對其自身以及競爭者在短期、長期股價報酬上之影響，運用了2009年至2019年間372筆產品召回事件進行實證分析。實證結果顯示產品召回對於宣告公司的短期股價，平均而言會有顯著的負累積平均異常報酬；而對於競爭者，平均將產生顯著的負累積平均異常報酬，然在事件日後的事件期間如(0~2)以及(1~2)則出現正累積平均異常報酬。在長期股價報酬影響部分，對於宣告公司平均而言則並沒有顯著之影響；而對生技醫療業與電腦及週邊設備業以外其他產業競爭者均產生了顯著的負累積平均異常報酬。另外，產品召回宣告公司比起競爭者公司，於短期事件期間具有顯著更低之累積異常報酬，最大幅度約為1%；然於長期事件期間兩者並無顯著差異。最後在橫斷面分析部分，股票週轉率、股票市值及股價淨值比都可在一定程度上解釋宣告公司以及其競爭者受到召回事件所影響之股價報酬變化。

This research is intended to investigate the impact of product recall announcement by Taiwan-listed companies on the short-term and long-term stock price returns of themselves and their competitors, using 372 product recall events in the 11 years from 2009 to 2019. The empirical results indicate that product recalls have a significant negative cumulative average abnormal return (CAAR) on the short-term stock price for the declared companies; while for competitors, producing a significant negative CAAR on average, but a significant positive CAAR also incurs for the period after the event, saying period (0~2) and (1~2). As for the long-term stock price, the recall events have no significant impact on the declared companies on average; however, a significant negative CAAR for competitors in industries other than the biotechnology and medical industry as well as computers and computing peripheral equipment industry is verified. Moreover, to the maximum, the declared companies have about 1% significant negative CAAR than their rivals in the short-term event period; while this significant difference doesn’t occur in the long-term period. Finally, the empirical results in the cross-sectional analysis part suggest that the stock turnover rate, stock market value and stock PB ratio can all explain the impact on stock price returns that the declared companies and their competitors received under the recall events.