The INVESTIGATION OF ASYMMETRIC DYNAMICS OF BORSA ISTANBUL INDEX WITH QUANTILE UNIT ROOT TEST

Abstract

In this study, we apply the quantile unit root test, which provides robust inferences for non-normal processes based on the quantile autoregression approach, to examine the asymmetric dynamic process of the BIST100 Borsa Istanbul index. The quantile autoregression approach allows the measurement of the persistency of shocks of different magnitudes and signs affecting the stock market index and can capture the adjustment of asymmetric dynamics in the long-run equilibrium of the index. Therefore, quantile unit root tests add new approaches to index dynamics compared to traditional unit root methodologies based on the least squares regression method. Our results show that the index not only returns to the mean but also exhibits asymmetric behavior in its dynamic structure. Compared to traditional unit root tests, quantile unit root tests provide more evidence to support the efficiency of the stock market index and show that the stock market index at different frequencies does not consistently have a unit root. Asymmetric inferences in shock magnitude and sign play an important role in asset pricing and forecasting in the securities market.