Panel Cointegration of Chinese A and B Shares

Abstract

In this paper we study market segmentation and information flows in China's stock markets. By using panel data methods we test for a unit root in the price premium of domestic investors' A shares over foreign investors' B shares as well as cointegration between the prices of the A and B shares on the Shanghai and Shenzhen stock exchanges. We find that the A-share premia are nonstationary and the A- and B-share prices are not cointegrated up till January 2001. After February 2001, when domestic investors were allowed to trade B shares, the A-share premia become stationary and the A- and B-share prices cointegrated. Our findings suggest that the relaxation of the investment restrictions decreased the information asymmetry betwen the A- and B-share markets in China.