新冠疫情對台灣四個產業之影響：事件研究與社群口碑

The Impact of COVID-19 Pandemic on Four Taiwan Industries: Event Study and Word-of-Mouth

本文首先探討新冠疫情事件對於台灣生技醫療業、觀光業、電腦及週邊設備業、航空運輸業等四個產業之影響，以2020年1月15日衛生福利部將新冠肺炎列為第五類法定傳染病之日作為事件日。結果顯示新冠疫情對於觀光業、電腦及週邊設備業，以及航空運輸業有負向影響，累積平均異常報酬大多為顯著負值。至於生技醫療業在事件日前累積平均異常報酬皆為負值，且大部分是顯著的；但在事件日之後，累積平均異常報酬幾乎都是正值，且到了較後期有呈現顯著正值。
接下來以迴歸分析探討在新冠疫情期間，來自社群口碑的網路聲量與情緒指標對於產業指數報酬之影響，研究結果發現正面情緒、正負情緒比與總聲量對於上櫃生技醫療業指數報酬有顯著正向影響；正面情緒與總聲量對於上市航空運輸業指數報酬有顯著正向影響；然而，網路聲量與情緒對於上市生技醫療業、上市（櫃）觀光業，以及上市（櫃）電腦及週邊設備業的指數報酬則無顯著影響。

This article firstly discussed the impact of COVID-19 pandemic on four industries including the biotechnology and medical care industry, tourism industry, computer and peripheral equipment industry, and shipping and transportation industry. The event day was January 15, 2020 which the Ministry of Health and Welfare declared that the COVID-19 was included in the fifth category of notifiable infectious disease. The results showed that the COVID-19 pandemic had a negative impact on the stock prices of tourism industry, computer and peripheral equipment industry, and shipping and transportation industry. And most of their CAARs were significantly negative. For the biotechnology and medical care industry, its CAARs were negative at pre-event windows, and most of them were significant; but its CAARs were positive at post-event windows, and they were significant at the later event windows.
Next, the impacts of internet volume and sentiment indicators of word-of-mouth on the returns of industrial sub-indices were examined by regression models during the COVID-19 outbreak. The results found that positive sentiment, positive-to- negative sentiment ratio, and total internet volume had significant positive impacts on the returns of OTC listed biotechnology and medical care sub-index. Positive sentiment and total internet volume had significant positive impacts on the returns of exchange listed shipping and transportation sub-index. However, internet volume and sentiment indicators did not have significant impacts on the returns of exchange listed biotechnology and medical care, exchange (OTC) listed tourism industry, and exchange (OTC) listed computer and peripheral equipment subindices.