Until recently the liquidity of financial assets has typically been viewed as a second-order consideration. Liquidity was frequently associated with simple transaction costs that impose - temporary if any- effect on asset prices, and whose shocks could be easily diversified away. Yet the...

This paper introduces a new class of observation-driven models, including score models as a special case. This new class inherits and extends the basic ideas behind the development of score models and addresses a number of unsolved issues in the score literature. In particular, the new class of...

This paper introduces a new class of observation-driven models, including score models as a special case. This new class inherits and extends the basic ideas behind the development of score models and addresses a number of unsolved issues in the score literature. In particular, the new class of...

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...