本研究目的為檢定台灣股票市場上市各產業類股的比價效應與新冠肺炎疫情影響下的比價效應，本研究採用Chang, Cheng和Khorana (2000)提出的CSAD (橫斷面離差絕對值cross-sectional absolute variance)來檢驗台灣股票市場各產業類股的比價效應。
本研究對象挑選為2021年1月至2022年1月共一年的平均各產業別股票當月成交金額占全體股票之比重前九大之類股作為研究對象。樣本期間為2017年1月21日至2023年1月20日共約六年的日資料取資料期間內所包含的研究對象經除權息調整的調整後收盤價。此區間為台灣確診首例日期2020年1月21日前後取三年來檢驗新冠疫情前後的比價效應。
研究實證結果顯示，在全資料期間中，整體市場產業除了金融保險類股外皆存在比價效應；在疫情前，整體市場全產業類股皆存在比價效應；在疫情後，整體市場之產業除金融保險類股、塑膠工業類股和電子業類股外皆存在比價效應。

The purpose of this study is to examine the intra-industry comparable price effect in the Taiwan stock market and the impact of COVID-19 on the intra-industry comparable price effect in the Taiwan stock market. The CSAD (cross-sectional absolute variance) is used to examine the intra-industry comparable price effect of each industry class in the Taiwan stock market.
The top nine industries were selected as the subjects of this study. The sample period is from January 21, 2017, to January 20, 2023. This period is three years before and after January 21, 2020, the date of the first confirmed case in Taiwan.
The empirical results of the study show that during the whole data period, intra-industry comparable price effect existed in all sectors of the market except for financial and insurance stocks.Before the epidemic, there was a price difference effect for all industry groups in the overall market.After the epidemic, there is a price difference effect in the overall market except for the financial and insurance sector, the plastics sector, and the electronics sector.

中文文獻
1. 江宏儒（2002）。股票市場從眾行為之探討：新興市場與已開發國家之比較〔未出版之碩士論文〕。國立高雄第一科技大學財務管理學所。
2. 陳志宏（2007）。台灣股市從眾行為之分析〔未出版之碩士論文〕。國立中山大學財務管理學系。
英文文獻
1. Asch, S. E. (1952). Group forces in the modification and distortion of judgments. In S. E. Asch, Social psychology,450–501.https://doi.org/10.1037/10025-016
2. Banerjee, A. (1992). A simple model of herd behavior. Quarterly Journal of Economics, 107, 797-817
3. Bikhchandani, S., & Sharma, S. (2000). Herd Behavior in Financial Markets. IMF Staff Papers, 47(3), 279–310. http://www.jstor.org/stable/3867650
4. Bikhchandani, S., Hirshleifer, D. and Welch, I. (1992) A Theory of Fads, Fashion, Custom, and Cultural Change as Informational Cascades. Journal of Political Economy, 100(5), 992-1026.https://doi.org/10.1086/261849
5. Chang, E. C., Cheng, J. W., & Khorana, A. (2000). An examination of herd behavior in equity markets: An international perspective. Journal of Banking & Finance, 24(10), 1651-1679. https://doi.org/10.1016/S0378-4266(99)00096-5
6. Chen, T. (2013). Do Investors Herd in Global Stock Markets? Journal of Behavioral Finance, 14(3), 230-239. https://doi.org/10.1080/15427560.2013.819804
7. Chiang, T. C., & Zheng, D. (2010). An empirical analysis of herd behavior in global stock markets. Journal of Banking & Finance, 34(8), 1911-1921. https://doi.org/10.1016/j.jbankfin.2009.12.014
8. Chiang, T. C., Li, J.-D. and Tan, L. (2010). Empirical investigation of herding behavior in Chinese stock market: Evidence from quantile regression analysis. Globla Finance Journal, 21, 111-124. https://doi.org/10.1016/j.gfj.2010.03.005
9. Christie, W. G., & Huang, R. D. (1995). Following the pied piper: Do individual returns herd around the market? Financial Analysts Journal, 51(4), 31-37. https://doi.org/10.2469/faj.v51.n4.1918
10. Economou, F., Kostakis, A., & Philippas, N. (2011). Cross-Country Effects in Herding Behaviour: Evidence from Four South European Markets. Journal of International Financial Markets, Institutions and Money, Forthcoming, 21(3), 443-460. https://doi.org/10.1016/j.intfin.2011.01.005
11. Galariotis, E. C., Rong, W., & Spyrou, S. I. (2015). Herding on fundamental information: A comparative study. Journal of Banking & Finance, 50, 589-598. https://doi.org/10.1016/j.jbankfin.2014.03.014
12. Hwang, S., & Salmon, M. (2004). Market stress and herding. Journal of Empirical Finance, 11(4), 585-616. https://doi.org/10.1016/j.jempfin.2004.04.003
13. Keynes, J. M., (1936). The General Theory of Employment, Interest and Money, Harcourt, Brace, and Co., New York.
14. Lakonishok, J., Shleifer, A., & Vishny, R. W., (1992). The Impact of Institutional Trading on Stock Prices. Journal of Financial Economics, 32, 23-43. https://doi.org/10.1016/0304-405X(92)90023-Q
15. Nofsinger, J.R. & Richard, W.S. (1999). Herding and Feedback Trading by Institutional and Individual Investors. The Journal of Finance, 54(6), 2263-2295.
16. Scharfstein, D. and Stein, J. (1990) Herd Behavior and Investment. American Economic Review, 80(3), 465-479.
17. Sharpe, W.F. (1964) Capital Asset Prices: A Theory of Market Equilibrium under Conditions of Risk. Journal of Finance, 19, 425-442.