Linear and nonlinear Granger causality test methods are used to detect the mean(return) and volatility(risk) spillover effects and their time-varying characteristics among the global main equity markets,including those in the U.S.,U.K.,Japan,Hong Kong and Mainland China.The empirical results indicate that: 1) There exist nonlinear mean/volatility spillover effects among the equity markets;2) The linkages among the equity markets are becoming more and more interactive and complex;3) The developme...