This paper studies the integrated Garch (IGARCH) e®ect, a phenomenon often encountered when estimating conditional auto-regressive models on ¯nancial time series. The analysis of twelve indexes of major ¯nancial markets provides empirical evidence of its well-spread presence especially in...

The paper investigates from an empirical perspective aspects related to the occurrence of the IGARCH effect and to its impact on volatility forecasting. It reports the results of a detailed analysis of twelve samples of returns on financial indexes from major economies (Australia, Austria,...