股吧投資專家對不同能力分析師盈餘預測偏誤影響之探究

近年來，隨著網路的普及，中國網路投資平台興起，股吧投資專家在論壇發表的投資意見備受投資人關注，對分析師而言形成一股競爭壓力。若股吧投資專家與分析師追蹤同一間公司，分析師可能有誘因為維護聲譽而提升盈餘預測準確度。本研究目的係檢視股吧投資專家首次加入有否影響到不同能力分析師之盈餘預測偏頗及盈餘預測錯誤。本研究將分析師盈餘預測偏頗區分樂觀偏頗或悲觀偏頗，實證結果顯示，在具有影響力股吧投資專家首次加入，相較於與其追蹤同一家公司之能力低的分析師，能力高分析師樂觀偏頗的幅度及悲觀偏頗的幅度均會顯著下降較多。實證結果亦顯示，當具有影響力股吧投資專家首次加入，追蹤同一家公司之能力佳分析師之盈餘預測錯誤會顯著減少。

關鍵字

股吧投資專家；分析師能力；盈餘預測偏頗改變；盈餘預測錯誤改變

並列摘要

In recent years, with the popularity of the Internet and the rise of online investment platforms in China, the investment opinions expressed by investment experts in Gub's forum have attracted attention from investors. Gub's statements create competitive pressure for analysts. If the investment experts on Gub's platform and analysts track the same company, the analysts may have incentives to improve the accuracy of their earnings forecasts for reputation. This study aims to examine whether forecast biases and forecast errors of analysts with different abilities will change after Gub's investment experts express their opinions on the same firm for the first time. This study differentiates analysts' earnings forecast bias into optimistic or pessimistic bias. Empirical results show that compared to analysts with low ability, both the magnitude of optimistic bias and pessimistic bias for analysts with high ability decreases significantly when influential investment experts express their opinion for the first time. Empirical results also show that earnings forecast errors of analysts with higher ability are significantly reduced when influential investment experts express their views for the first time at the same firm that analysts follow.