Time-varying Informational Efficiency in China's A-Share and B-Share Markets

This paper employs a time-varying framework to examine the informational efficiency of China's A-share and B-share markets, with a focus placed on the following issues: changing weak-form efficiency, the leverage effect, and information transmission in return volatility. We find that the A-share markets perform better than the B-share markets in terms of efficiency-improving; significant leverage effects exist in three of four markets but with different signs; and no weak and strong volatility transmissions characterise different pairs of markets. Market segmentation is also documented, as evidenced by no co-movements in the long-run behaviour of the four Chinese share markets.