We discuss several multivariate extensions of the Multiplicative Error Model to take into account dynamic interdependence and contemporaneously correlated innovations (vector MEM or vMEM). We suggest copula functions to link Gamma marginals of the innovations, in a specification where past...

The Multiplicative Error Model for nonnegative valued processes is specified as the product of a (conditionally autoregressive) scale factor and an innovation process with nonnegative support. A multivariate extension allows the innovations to be contemporaneously correlated. The estimation...

The inverse relation between stock returns and their volatility, known as volatility leverage-effect (VLE), is documented as a strikingly robust empirical regularity. This paper argues that existing explanations of the phenomenon either suffer from logical inconsistencies or have secondary...