This paper considers a class of finite-order autoregressive linear ARCH models. The model captures the leverage effect, allows the volatility to be arbitrarily close to zero and to reach its minimum for non-zero innovations, and is appropriate for long-memory modeling when infinite orders are...

This paper considers a class of finite-order autoregressive linear ARCH models. The model captures the leverage effect, allows the volatility to be arbitrarily close to zero and to reach its minimum for non-zero innovations, and is appropriate for long-memory modeling when infinite orders are...

The asymptotic distribution of the QML estimator for GARCH processes, with coefficients possibly equal to zero, is established. This distribution is the projection of a normal vector distribution onto a convex cone. The results are derived under mild conditions which, for important subclasses,...