leverage effect and the volatility feedback effect. We stress the importance of distinguishing between realized volatility and … implied volatility, and find that implied volatilities are essential for assessing the volatility feedback effect. The … leverage hypothesis asserts that return shocks lead to changes in conditional volatility, while the volatility feedback effect …

data to test for nonlinear leverage versus volatility feedback effects and to test for causality between stock returns and …

transaction durations and vice versa. Otherwise the spacings between trades are considered exogenous to the volatility dynamics … causality between volatility and intra-trade durations. Under general conditions we propose several GMM estimation procedures … that volatility of IBM stock prices Granger causes intra-trade durations. We also find that the persistence in GARCH drops …

leverage, volatility and the riskless interest rate. We find that estimated coefficients for these variables are consistent … premia is approximately 23%. Volatility and leverage by themselves also have substantial explanatory power for credit default … data. We therefore conclude that leverage, volatility and the riskfree rate are important determinants of credit default …