English Abstract: To explain excess volatility frequently observed in asset markets, this paper suggests that the time … volatility clustering. Reflecting the realistic assumptions, this paper also extends the heterogeneous agent models, and … behavior causes excess volatility as well as volatility clustering, and plays an influential role in dynamics of asset prices …

English Abstract: This paper suggests a dynamic measure of intentional herding, causing the excess volatility or even … herding on market volatility tends to be stronger during the periods of turbulent markets like the degradation of U …