This paper studies the information spillover effects among KOSPI 200, corporate bond interest rate, construction industry index using the daily data from December 30, 2014 to April 18, 2025 with granger-causality test, GARCH(1,1)-M model, GJR-GARCH(1,...
This paper studies the information spillover effects among KOSPI 200, corporate bond interest rate, construction industry index using the daily data from December 30, 2014 to April 18, 2025 with granger-causality test, GARCH(1,1)-M model, GJR-GARCH(1,1)-M model. In addition, the sample is divided into two sub-samples to verify the changes in the information spillover effects before and after COVID-19. The pre-Covid-19 period is from December 30, 2014 to March 19, 2020, and the post-Covid-19 period is from March 20, 2020 to April 18, 2025. The main results are as follows.
First, the standard deviation of the construction industry index returns was highest and all samples don’t follow the normal distribution process. The cross-correlations between the returns of the construction industry index and those of KOSPI 200 were high.
Second, from the granger-causality test, there were feedback information spillover effects between the construction industry index returns and the KOSPI 200 returns as well as between the construction industry index returns and the corporate bond interest rate returns. And there was the information spillover effects from KOSPI 200 returns to corporate bond interest rate returns.
Third, from the GARCH(1,1)-M model, the whole period, the pre-COVID-19 period, and the post-COVID-19 period showed predictive power in returns and volatility between the KOSPI 200 and the construction industry index. There was the predictive power by only the rate of return in the whole period and the pre-COVID-19 period between the corporate bond interest rate and the construction industry index each other. But there were no feedback influences in the post-COVID-19 period. The KOSPI 200 returns was predictable for the bond interest rate returns over the whole period and also, both returns and volatilities of the bond interest rate were predictable for the KOSPI 200 returns over the whole period. Although the predictive power between the KOSPI 200 returns and the bond interest rate appeared in the pre-COVID-19 period, it disappeared in the post-COVID-19 period.
Fourth, According to the analysis of the GJR-GARCH (1,1)-M model, the information spillover effects between the KOSPI 200 and the construction industry index happened by the bad news from the whole period, the pre-COVID-19 period and the post-COVID-19 period. The feedback information spillover effects between the corporate bond rate returns and the construction industry index returns were due to both bad news and good news in the whole period. In the pre-COVID-19, the bad news on the past corporate bond rate affected the construction industry index, while the good news on the past construction industry index affected the return on corporate bond rates. The information spillover effects between the KOSPI 200 returns and the corporate bond rate returns were mainly due to bad news in the past.
The implications and limitations of this study can be summarized as follows. First of all, the information spillover effects between the corporate bond rate and the construction industry index as well as the KOSPI 200 and the corporate bond returns almost disappeared in the post -COVID-19 period compared to the pre-COVID-19 period. This is inferred to be due to the downturn in the construction industry. Considering the fact that the construction industry has a profound effect on the overall industry and the employment index, there is an urgent need to stimulate the construction economy, which has stagnated after COVID-19.
As a limitation, there may be various macro and micro variables that affect the construction industry, and these variables are not widely considered. Further research needs to add various variables that can affect the construction industry. In addition, it is necessary to include in the analysis when the construction economy is stimulated in the future in order to derive consistent results and implications.