台灣個別投資人之重購行為研究

Abstract

這篇論文利用投資人整體投資次數以及投資人比例兩種角度，來探討台灣投資人的三種重購行為，(1)是否會重購之前賣出時獲利的股票；(2)是否會重購賣出後價格下跌的股票以及(3)是否會重購目前持有的投資組合中，價格下跌的股票，根據研究發現，投資人確實有這些傾向；並且取1998年至2001年的台灣股票市場加權指數資料發現，投資人在市場景氣低迷時，會更傾向於做這些重購動作。 另外根據研究顯示，投資人無法從這些重購行為中獲利，而在利用回歸分析後，也找出一些從事這些重購行為投資人的特性。

This paper documents individual investors may be affected by their prior trading experience while they buying stocks. Individual investors have three patterns of repurchasing stocks. They prefer to (1) repurchase stocks that previously sold for a gain, (2) repurchase stocks that have decreased in price since the last sale, (3) purchase additional shares of stocks that have drop in price. This study also tries to figure out how individual investors and which group of individual investors are affected by the mental factor and will they profit from this form of learning. Unlike what U.S. investors’ behave, Taiwanese individual investors do not appear the same preference in the total trading frequency. Investors who repurchase prior losers and stocks that have gone up in price may trade more and it causes that there is almost no difference in the total trading frequency made by investors who repurchase prior winners which have gone down in price and by investor who repurchase prior losers which have gone up in price. This paper also discovers that investors trade more aggressively when stock market is not in the good situation. Moreover, the proportion of investors who repurchase prior winners and investors who repurchase stocks lost in value also rise in this phase. Furthermore, the paper finds that investors hardly make profit by doing activities which were discussed above and figure out the characteristics of the investors who act these behaviors.