crashes, excess volatility, serially uncorrelated returns, fat-tailed return distributions and volatility clustering, thereby …, speculators' heterogeneity occasionally vanishes, e.g. due to panic-induced herding behavior, yielding extreme returns. Lasting … regimes with high volatility originate from the fact that speculators extract stronger trading signals out of past stock price …

pricing models postulate a positive relationship between a stock portfolio’s expected returns and risk, which is often … relationship between mean returns on the Nigeria commercial banks portfolio investments and its conditional variance or standard … volatility, while the EGARCH model gives a negative relationship. We suggest that market operators should try as much as possible …