Stock returns and volatility: the Brazilian case

摘要

This paper examines the relationship between stock returns and volatility over the period of June 1990 to April 2002. We study firm-level relationship between stock returns and volatility for a sample of 25 time series of Brazilian stocks. Using Seemingly Unrelated Regressions (SUR) empirical evidence suggests that contemporaneous returns and volatilities are significantly and positively correlated while there is a negative relationship between changes in volatility and stock returns. Finally, the asymmetric volatility effect seems to hold for Brazilian stocks as shown by the results from an AR(1)-EGARCH(1,1) estimation.