A class of stochastic unit-root bilinear processes, allowing for GARCH-type effects with asymmetries, is studied. The volatility is not bounded away from zero and is minimum for non zero innovations, which are important differences with the standard GARCH. Necessary and sufficient conditions for...

The paper considers the question of dominance, in the context of financial markets, of the deterministic unit root processes with a structural break by the bilinear unit root model without such break or vice versa. In the deterministic unit root process breaks are usually interpreted as...