THE IMPACT OF FOREIGN INVESTORS' ABNORMAL TRADING ON THE ABNORMAL RETURNS OF BANKING SECTOR STOCKS: THE CASE OF VIETNAM
DOI:
https://doi.org/10.33736/ijbs.9543.2025Keywords:
Foreign investors, abnormal trading, abnormal return, banking sector, VietnamAbstract
This study aims to analyze the impact of foreign investors' abnormal trading on the abnormal returns of banking sector stocks in Vietnam from 2006 to 2023. The data sample includes 631 abnormal buy events, 571 abnormal buy events on net purchase days, 477 abnormal sell events, and 432 abnormal sell events on net sell days of foreign investors. The study employs the event study methodology with parametric and non-parametric tests. The results show that abnormal buy events and abnormal buy events on net purchase days by foreign investors convey positive information and have a positive impact on stock prices, creating positive abnormal returns, with stock prices forming new equilibrium levels. Abnormal sell events and abnormal sell events on net sell days convey negative information and have a negative impact on stock prices in the short term, after which prices tend to return to their initial states as before the events. The study suggests that investors can observe foreign investors' trading behavior as reference information in their investment decisions regarding banking sector stocks. Furthermore, it recommends that the government consider relaxing the "room" limit on foreign ownership in Vietnamese commercial banks to align with the objective of upgrading the stock market.
References
Abdulkadir, R. I. (2023). A test of positive feedback trading among foreign portfolio investors in Nigeria. Gadjah Mada International Journal of Business, 25(3), 279-300.
https://doi.org/10.22146/gamaijb.69984
Angelovska, J. (2020). The Impact of Foreigners' Trades on Equity Prices: Evidence from Macedonian Stock Exchange. South East European Journal of Economics and Business, 15(1), 56-65.
https://doi.org/10.2478/jeb-2020-0005
Bajo, E. (2010). The information content of abnormal trading volume. Journal of Business Finance & Accounting, 37(7‐8), 950-978.
https://doi.org/10.1111/j.1468-5957.2010.02197.x
Blume, L., Easley, D., & O'hara, M. (1994). Market statistics and technical analysis: The role of volume. The journal of finance, 49(1), 153-181. Bolaman Avcı, Ö. (2015). Effect of foreign investor transactions on stock market returns. Hacettepe University Journal of Economics and Administrative Sciences, 33(4), 29-38.
https://doi.org/10.1111/j.1540-6261.1994.tb04424.x
Bonnier, K.-A., & Bruner, R. F. (1989). An analysis of stock price reaction to management change in distressed firms. Journal of Accounting and Economics, 11(1), 95-106.
https://doi.org/10.1016/0165-4101(89)90015-3
Brown, S. J., & Warner, J. B. (1985). Using daily stock returns: The case of event studies. Journal of Financial Economics, 14(1), 3-31.
https://doi.org/10.1016/0304-405X(85)90042-X
Bui, T. (2020). Stock holding decisions of foreign investors in emerging stock markets: A case study in Vietnam. Management Science Letters, 10(3), 625-630.
https://doi.org/10.5267/j.msl.2019.9.017
Chhimwal, B., & Bapat, V. (2020). Impact of foreign and domestic investment in stock market volatility: Empirical evidence from India. Cogent Economics & Finance, 8(1), 1754321.
https://doi.org/10.1080/23322039.2020.1754321
Cho, J.-H. (2021). Effect of Foreign Investors' Trade Amount by Nationality on Korean Stock Market. Journal of Digital Convergence, 19(8), 161-171.
Clark, P. K. (1973). A subordinated stochastic process model with finite variance for speculative prices. Econometrica: Journal of the Econometric Society, 41(1), 135-155.
https://doi.org/10.2307/1913889
Dahlquist, M., & Robertsson, G. (2004). A note on foreigners' trading and price effects across firms. Journal of Banking & Finance, 28(3), 615-632.
https://doi.org/10.1016/S0378-4266(03)00036-0
Danila, N., Bunyamin, Djalaluddin, A., & Fathony, Y. (2023). Do Foreign Fund Flows Influence the Stock Market Index? Evidence From Indonesia. SAGE Open, 13(4), 1-9. https://doi.org/10.1177/21582440231201485
https://doi.org/10.1177/21582440231201485
Ding, D. K., & Sun, Q. (1997). The information content of FDI announcements: evidence from an emerging market. International Review of Financial Analysis, 6(1), 63-76.
https://doi.org/10.1016/S1057-5219(97)90020-X
Gupta, S., Kalra, N., & Bagga, R. (2013). Impact of foreign investments on stock market volatility: An evidence from Indian Stock Market. Effective Management, 1, 1-13.
Harris, L., & Gurel, E. (1986). Price and volume effects associated with changes in the S&P 500 list: New evidence for the existence of price pressures. The Journal of Finance, 41(4), 815-829.
https://doi.org/10.1111/j.1540-6261.1986.tb04550.x
Hartmann, D., & Pierdzioch, C. (2007). International equity flows and the predictability of US stock returns. Journal of Forecasting, 26(8), 583-599.
https://doi.org/10.1002/for.1045
He, W., & Shen, J. (2014). Do foreign investors improve informational efficiency of stock prices? Evidence from Japan. Pacific-Basin Finance Journal, 27, 32-48.
https://doi.org/10.1016/j.pacfin.2014.01.005
Homan, A. C. (2006). The impact of 9/11 on financial risk, volatility and returns of marine firms. Maritime Economics & Logistics, 8, 387-401.
https://doi.org/10.1057/palgrave.mel.9100165
Huang, Z.-x., Tang, Q., & Huang, S. (2020). Foreign investors and stock price crash risk: Evidence from China. Economic Analysis and Policy, 68, 210-223.
https://doi.org/10.1016/j.eap.2020.09.016
Jarrell, G. A., & Poulsen, A. B. (1989). Stock trading before the announcement of tender offers: insider trading or market anticipation? The Journal of Law, Economics, and Organization, 5(2), 225-248.
Kartal, M. T., Ertuğrul, H. M., & Ulussever, T. (2022). The impacts of foreign portfolio flows and monetary policy responses on stock markets by considering COVID-19 pandemic: Evidence from Turkey. Borsa Istanbul Review, 22(1), 12-19.
https://doi.org/10.1016/j.bir.2021.06.003
Kim, H., & Park, S. (2017). The effects of foreign investors on firms' crash risk. Korean Journal of Financial Studies, 46(4), 839-877.
https://doi.org/10.26845/KJFS.2017.09.46.4.839
Lambertides, N. (2009). Sudden CEO vacancy and the long‐run economic consequences. Managerial Finance, 35(7), 645-661.
https://doi.org/10.1108/03074350910960364
Lamoureux, C. G., & Lastrapes, W. D. (1990). Heteroskedasticity in stock return data: Volume versus GARCH effects. The Journal of Finance, 45(1), 221-229. Lummer, S. L., & McConnell, J. J. (1989). Further evidence on the bank lending process and the capital-market response to bank loan agreements. Journal of Financial Economics, 25(1), 99-122.
https://doi.org/10.1111/j.1540-6261.1990.tb05088.x
MacKinlay, A. C. (1997). Event studies in economics and finance. Journal of Economic Literature, 35(1), 13-39.
Malik, I. A., & Amjad, S. (2013). Foreign direct investment and stock market development in Pakistan. Journal of International Trade Law and Policy, 12(3), 226-242.
https://doi.org/10.1108/JITLP-02-2013-0002
Petajisto, A. (2011). The index premium and its hidden cost for index funds. Journal of empirical Finance, 18(2), 271-288.
https://doi.org/10.1016/j.jempfin.2010.10.002
Phan, T. N. T., Bertrand, P., Phan, H. H., & Vo, X. V. (2023). The role of investor behavior in emerging stock markets: Evidence from Vietnam. The Quarterly Review of Economics and Finance, 87, 367-376.
https://doi.org/10.1016/j.qref.2021.07.001
Phansatan, S., Powell, J. G., Tanthanongsakkun, S., & Treepongkaruna, S. (2012). Investor type trading behavior and trade performance: Evidence from the Thai stock market. Pacific-Basin Finance Journal, 20(1), 1-23.
https://doi.org/10.1016/j.pacfin.2011.07.004
Richards, A. (2005). Big fish in small ponds: The trading behavior and price impact of foreign investors in Asian emerging equity markets. Journal of Financial and Quantitative Analysis, 40(1), 1-27.
https://doi.org/10.1017/S0022109000001721
Sapian, R. Z. Z., & Auzairy, N. A. (2015). Foreign equity flows and market return linkages: Evidence of Malaysian stock market. Global Business Review, 16(5_suppl), 1S-14S.
https://doi.org/10.1177/0972150915601233
Suominen, M. (2001). Trading volume and information revelation in stock market. Journal of Financial and Quantitative Analysis, 36(4), 545-565.
https://doi.org/10.2307/2676224
Tsagkanos, A., Siriopoulos, C., & Vartholomatou, K. (2019). Foreign direct investment and stock market development: Evidence from a "new" emerging market. Journal of Economic Studies, 46(1), 55-70.
https://doi.org/10.1108/JES-06-2017-0154
Tudor, C. (2021). Investors' Trading Activity and Information Asymmetry: Evidence from the Romanian Stock Market. Risks, 9(8), 149. https://www.mdpi.com/2227-9091/9/8/149
https://doi.org/10.3390/risks9080149
Ülkü, N., & İkizlerli, D. (2012). The interaction between foreigners' trading and emerging stock returns: Evidence from Turkey. Emerging Markets Review, 13(3), 381-409.
https://doi.org/10.1016/j.ememar.2012.06.002
Vo, X. V. (2010). Foreign ownership in Vietnam stock markets-an empirical analysis. MPRA Working Paper.
Vo, X. V. (2016). Foreign ownership and stock market liquidity-evidence from Vietnam. Afro-Asian Journal of Finance and Accounting, 6(1), 1-11.
https://doi.org/10.1504/AAJFA.2016.074540
Vo, X. V. (2017a). Do foreign investors improve stock price informativeness in emerging equity markets? Evidence from Vietnam. Research in International Business and Finance, 42, 986-991.
https://doi.org/10.1016/j.ribaf.2017.07.032
Vo, X. V. (2017b). Trading of foreign investors and stock returns in an emerging market-Evidence from Vietnam. International Review of Financial Analysis, 52, 88-93.
https://doi.org/10.1016/j.irfa.2017.05.007
Vo, X. V. (2019). Do foreign investors promote stock price efficiency in emerging markets? International Review of Finance, 19(1), 223-235.
https://doi.org/10.1111/irfi.12164
Vo, X. V., & Dang, B. K. (2016a). Information content of foreign investor trading: Empirical investigation in the Ho Chi Minh city Stock Exchange. Journal of Economics and Development, 225, 46-55.
Vo, X. V., & Dang, B. K. (2016b). Stock Market Reaction to the Announcement of Changes in the VNM - Empirical Investigation in the Vietnamese Stock Market. VNU Journal of Economics and Business, 32(3), 18-27. Vo, X. V., & Dang, B. K. (2016c). Stock market reaction to the news of inclusion/exclusion of stocks in FTSE portfolio: Empirical investigation in the Vietnamese Stock Market. Journal of Economics and Development, 223, 41-50.
Wright, C., & Swidler, S. (2023). Abnormal trading volume, news and market efficiency: Evidence from the Jamaica Stock Exchange. Research in International Business and Finance, 64, 101804.
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