Information Diffusion and Overreaction: Evidence from the Chinese Stock Market

Abstract

This paper empirically examines the relation between overreaction and the speed of information diffusion in the Chinese stock market. Industry-adjusted firm size and residual analyst coverage are used to proxy the speed of information diffusion. We document strong evidence that the profitability of a monthly contrarian strategy decreases with industry-adjusted firm size or residual analyst coverage. Moreover, the profitability of contrarian strategies survives for a longer horizon for stocks with slower information diffusion than for those with faster information diffusion. This result holds true even if risk, bid-ask spread, lead-lag effect, inventory costs, and limits to arbitrage are properly accounted for. Our findings suggest that information environment and information diffusion determine the extent of overreaction.

Keywords:

• Chinese stock market
• contrarian strategy
• information diffusion
• overreaction