Stock Market Integration, Return Forecastability and Implications for Market Efficiency: A Panel Study

Using a panel data set for 18 stock countries, this paper finds fairly strong integration among national equity markets. A country's stock index price can be decomposed into a common trend component and a stationary country-specific component. Results show that the 18 country indexes reverse to the world trend with a speed of 18% per year, and that the Hong Kong market converges to other markets with a speed of 22% per year or a half life of …