本研究利用迴歸分析探討三大法人和散戶對台積電的買賣超的資訊內涵。期間因疫情的發生又將實證期間分為二個階段。分別以2020年3月30日為分界點來檢視疫情前後法人及散戶對台積電的買賣超是否對台灣加權及ETF 0050有其資訊內涵。 實證結果發現,外資對台積電的買賣超與散戶一樣對報酬有顯著負相關,推測外資在投資台積電時是屬於長期波段投資,受疫情之後大漲而賣出獲利。而在疫情發生之後,外資與投信的台積電買賣超對大盤的解釋力消失,反而是自營商的台積電買賣超對大盤具有顯著的解釋能力,而散戶則是一直都是負向相關。 ;This study uses the general least squares method to explore the over-trading behaviors of the three institutional investors and retail investors on TSMC in the exchanges in the past 10 years; the empirical period is divided into two stages due to the outbreak of the epidemic. Take March 30, 2020 as the cut-off point to examine whether the trading of TSMC by three institutional investors and retail investors before and after the epidemic is overweight to TWSE of Taiwan and whether ETF 0050 has its informational connotations. From the empirical results, it is found that in the whole period of the empirical study, foreign investment in TSMC is significantly negatively correlated with retail investors. It is speculated that foreign investment in TSMC is a long-term investment. After the outbreak of the epicemic, the explanatory power of foreign capital and investment trust TSMC trading super to the broader market disappeared. On the contrary, after the epidemic, the porprietary TSMC trading super had Significant explanatory power to the broader market. Retail investors have always been negatively correlated.