코로나19 사태 전후 미국 주식시장의 정보이전현상과 외국계투자자의 매매행태에 관한 연구

Abstract

This study analyzed whether there was any change during this period in the information transfer phenomenon of the US stock market to the domestic stock market by dividing it into before and after the outbreak of the corona crisis. Also, during this period, we looked at the changes in the impact of foreign investors’ trading behavior on the domestic stock market. The period for the empirical analysis was from January 2, 2017 to June 17, 2022, and March 11, 2020, when the WHO declared a pandemic, was used as the reference point for the distinction between before and after the outbreak of COVID-19. The main analysis results are as follows. First of all, it was confirmed that the same information transfer phenomenon occurs in the US stock market in terms of yield and volatility in the domestic stock market as in previous studies. However, in the case of the transfer of the return of the domestic stock market to the US stock market, the night return showed a strong effect, but the weekly return showed the opposite result. Therefore, it was found that the domestic stock market overreacted to the US market at the beginning of the day and then went through an adjustment process during the day. No significant differences were found when comparing the domestic nighttime and weekly returns before and after the corona crisis regarding the yield transfer phenomenon from the US market. Second, the trading behavior of foreign investors was found to have a positive (+) effect on the domestic stock market, as expected. When net purchases by foreign investors have a positive (+) value, the KOSPI, as well as large-cap, mid-cap, and small-cap stock indices generally rise. Unlike before and after the outbreak of COVID-19, foreign investors’ trading behavior continued to show an advantage over significant selling, but in terms of their influence on the domestic stock market, no significant difference could be found before and after the outbreak of COVID-19. However, before the outbreak of COVID-19, most indices showed a positive (+) relationship between the nightly yield and the trading behavior of foreign investors, but after that, there was no statistical significance between them. The results of this study are meaningful in that the movements of the US stock market and the trading behavior of foreign investors after the COVID-19 crisis provide important information to investors participating in the domestic capital market in making investment decisions.