散戶投資人在同股票與產業交易經驗的學習效果

相較於過去投資組合的實證方法，本研究以台灣股票市場整體散戶投資人為研究對象，探討散戶投資人過去在相同股票或產業的交易經驗對於未來個股交易行為與投資績效的影響，以檢測散戶投資人過去在個股或產業的交易是否存在學習效果。實證結果發現，當散戶投資人過去在同股票或產業的交易經驗愈多時，未來在個股的交易行為會顯著增加，且未來的投資績效也會顯著提高，說明了散戶投資人在同股票與產業學習效果的存在；另外本研究也發現散戶投資人的學習效果會隨著時間遞減。進一步依據不同投資人特徵以及個股特徵做分組後，結果發現相對於積極的散戶投資人，非積極的散戶投資人過去在個股與產業的學習效果較為顯著；另外相對於大公司與電子股公司而言，散戶投資人過去在小公司與非電子股公司的學習效果較為顯著。

關鍵字

散戶投資人；學習效果；過度自信；行為財務學

並列摘要

Relative to viewpoint of portfolio in existing researches, we examine whether the individual investors could learn from trading experience of the same stock and industry to improve their trading behavior or performance in the future. The empirical results indicate that more trading experience in the same stock and industry of a individual investor, the more incentive to trade the same stock and the trading performance will be better. Our results support that there exists learning effect of individual investors in the same stock and industry. We also find that the learning effect of individual investor is decreased over time. Finally, after categorize by characteristics of investors and individual stock, we find that the learning effect is more significant in inactive investors than active investors. In addition, the learning effect of individual investor is more significant in small companies and non-electrical companies.